Annular flow optimization: A new integrated approach
Maglione, R.; Robotti, G.; Romagnoli, R.
1997-07-01
During the drilling stage of an oil and gas well the hydraulic circuit of the mud assumes great importance with respect to most of the numerous and various constituting parts (mostly in the annular sections). Each of them has some points to be satisfied in order to guarantee both the safety of the operations and the performance optimization of each of the single elements of the circuit. The most important tasks for the annular part of the drilling hydraulic circuit are the following: (1) Maximum available pressure to the last casing shoe; (2) avoid borehole wall erosions; and (3) guarantee the hole cleaning. A new integrated system considering all the elements of the annular part of the drilling hydraulic circuit and the constraints imposed from each of them has been realized. In this way the family of the flow parameters (mud rheology and pump rate) satisfying simultaneously all the variables of the annular section has been found. Finally two examples regarding a standard and narrow annular section (slim hole) will be reported, showing briefly all the steps of the calculations until reaching the optimum flow parameters family (for that operational condition of drilling) that satisfies simultaneous all the flow parameters limitations imposed by the elements of the annular section circuit.
Transient Response of Shells of Revolution by Direct Integration and Modal Superposition Methods
NASA Technical Reports Server (NTRS)
Stephens, W. B.; Adelman, H. M.
1974-01-01
The results of an analytical effort to obtain and evaluate transient response data for a cylindrical and a conical shell by use of two different approaches: direct integration and modal superposition are described. The inclusion of nonlinear terms is more important than the inclusion of secondary linear effects (transverse shear deformation and rotary inertia) although there are thin-shell structures where these secondary effects are important. The advantages of the direct integration approach are that geometric nonlinear and secondary effects are easy to include and high-frequency response may be calculated. In comparison to the modal superposition technique the computer storage requirements are smaller. The advantages of the modal superposition approach are that the solution is independent of the previous time history and that once the modal data are obtained, the response for repeated cases may be efficiently computed. Also, any admissible set of initial conditions can be applied.
NASA Technical Reports Server (NTRS)
Jones, J. E.; Richmond, J. H.
1974-01-01
An integral equation formulation is applied to predict pitch- and roll-plane radiation patterns of a thin VHF/UHF (very high frequency/ultra high frequency) annular slot communications antenna operating at several locations in the nose region of the space shuttle orbiter. Digital computer programs used to compute radiation patterns are given and the use of the programs is illustrated. Experimental verification of computed patterns is given from measurements made on 1/35-scale models of the orbiter.
NASA Astrophysics Data System (ADS)
Mateescu, D.; Païdoussis, M. P.; Belanger, F.
1994-07-01
The paper presents 2-D and 3-D computational solutions for unsteady annular viscous flows with oscillating boundaries. A time-integration method based on a three-time-level implicit semi-discretization is first formulated in cylindrical coordinates for solving the time-dependent incompressible Navier-Stokes equations. This methods uses a pseudo-time integration with artificial compressibility to advance the solution between consecutive real time levels, and a finite-difference spatial discretization based on a stretched staggered grid. A decoupling procedure based on a factored ADI scheme with lagged nonlinearities reduces the problem to the solution of scalar tridiagonal systems. As a result, this method displays very good computing efficiency and accuracy in all numerical examples analysed. The method is first validated for axisymmetric flow over an annular backstep, by comparison with previous results, and is then employed to analyse 2-D unsteady annular flows due to transverse oscillations of the outer boundary. The results obtained with this method are free of spurious, numerically induced, oscillations in the unsteady pressure, which otherwise arise if a Crank-Nicolson scheme is used instead for time-discretization.The 3-D case of oscillating boundaries in annular axial flow is also analysed with this method by considering a fully developed viscous axial flow between two concentric cylinders when the central portion of the outer cylinder executes transverse translational oscillations; the computational solution thus obtained is of interest in the study of flow-induced vibration problems in such configurations.
... page: //medlineplus.gov/ency/article/001142.htm Annular pancreas To use the sharing features on this page, please enable JavaScript. An annular pancreas is a ring of pancreatic tissue that encircles ...
NASA Technical Reports Server (NTRS)
Tschunko, H. F. A.
1983-01-01
Reference is made to a study by Tschunko (1979) in which it was discussed how apodization modifies the modulation transfer function for various central obstruction ratios. It is shown here how apodization, together with the central obstruction ratio, modifies the point spread function, which is the basic element for the comparison of imaging performance and for the derivation of energy integrals and other functions. At high apodization levels and lower central obstruction (less than 0.1), new extended radial zones are formed in the outer part of the central ring groups. These transmutation of the image functions are of more than theoretical interest, especially if the irradiance levels in the outer ring zones are to be compared to the background irradiance levels. Attention is then given to the energy distribution in point images generated by annular apertures apodized by various transmission functions. The total energy functions are derived; partial energy integrals are determined; and background irradiance functions are discussed.
Internal combustion engine with a central crankshaft and integral tandem annular pistons
NASA Astrophysics Data System (ADS)
Esparbes, Bernard
1993-08-01
An internal combustion engine with tandem annular pistons and a central crankshaft is disclosed, based on that found in British patent 11027 of 11 May 1914. The piston block formed by the two pistons presents, at each axial extremity, a double axial skirt fitted with an outer crown forming the head of the piston as such, and an inner crown forming an inlet pump with a holding chamber radially located at the inside of the corresponding annular cylinder, in which the piston head delimits a combustion chamber. Radial fingers, crossing axial openings of the crankcase and radial holes of the piston block, have their inner radial ends engaged within wavy sinusoidal peripheral slots arranged in a bulging central portion of the central crankshaft set into rotation by alternating axial movements of the piston block. The admission of fuel or combustion sustaining gas is ensured axially by the extremities, valves, and openings in the end plates closing the holding chambers in which the inner crowns slide, fitted with valves to act as an inlet pump. The invention is particularly applicable to aircraft engines in view of the ease in which the shaft rotation can be adapted to such a use.
Gupta, Diptesh; Hess, Brian; Bachegowda, Lohith
2010-01-01
We present a case of a 77-year-old, diabetic male with a 20-year history of a migratory erythematous, asymptomatic, generalized, nonscaly, and nonitchy rash that started over the dorsum of his left hand. On examination, there were multiple annular erythematous plaques, distributed symmetrically and diffusely over his torso and arms, with central clearing and no scales. A punch biopsy of the skin helped us to arrive at the diagnosis of a generalized granuloma annulare (GA). GA is a benign, self-limiting skin condition of unknown etiology that is often asymptomatic. The cause of this condition is unknown, but it has been associated with diabetes mellitus, infections such as HIV, and malignancies such as lymphoma. These lesions typically start as a ring of flesh-colored papules that slowly progress with central clearing. Lack of symptoms, scaling, or associated vesicles helps to differentiate GA from other skin conditions such as tinea corporis, pityriasis rosea, psoriasis, or erythema annulare centrifugum. Treatment is often not needed as the majority of these lesions are self-resolving within 2 years. Treatment may be pursued for cosmetic reasons. Available options include high-dose steroid creams, PUVA, cryotherapy, or drugs such as niacinamide, infliximab, Dapsone, and topical calcineurin inhibitors. PMID:20209383
Multipartite entanglement of superpositions
NASA Astrophysics Data System (ADS)
Cavalcanti, D.; Terra Cunha, M. O.; Acín, A.
2007-10-01
The entanglement of superpositions [Linden , Phys. Rev. Lett. 97, 100502 (2006)]is generalized to the multipartite scenario: an upper bound to the multipartite entanglement of a superposition is given in terms of the entanglement of the superposed states and the superposition coefficients. This bound is proven to be tight for a class of states composed of an arbitrary number of qubits. We also extend the result to a large family of quantifiers, which includes the negativity, the robustness of entanglement, and the best separable approximation measure.
Multipartite entanglement of superpositions
Cavalcanti, D.; Terra Cunha, M. O.; Acin, A.
2007-10-15
The entanglement of superpositions [Linden et al., Phys. Rev. Lett. 97, 100502 (2006)]is generalized to the multipartite scenario: an upper bound to the multipartite entanglement of a superposition is given in terms of the entanglement of the superposed states and the superposition coefficients. This bound is proven to be tight for a class of states composed of an arbitrary number of qubits. We also extend the result to a large family of quantifiers, which includes the negativity, the robustness of entanglement, and the best separable approximation measure.
PIEPHO, M.G.
2000-01-10
Four bounding accidents postulated for the K West Basin integrated water treatment system are evaluated against applicable risk evaluation guidelines. The accidents are a spray leak during fuel retrieval, spray leak during backflushing a hydrogen explosion, and a fire breaching filter vessel and enclosure. Event trees and accident probabilities are estimated. In all cases, the unmitigated dose consequences are below the risk evaluation guidelines.
RITTMANN, P.D.
1999-10-07
Three bounding accidents postdated for the K West Basin integrated water treatment system are evaluated against applicable risk evaluation guidelines. The accidents are a spray leak during fuel retrieval, spray leak during backflushing, and a hydrogen explosion. Event trees and accident probabilities are estimated. In all cases, the unmitigated dose consequences are below the risk evaluation guidelines.
Keimig, Emily Louise
2015-07-01
Granuloma annulare (GA) is a noninfectious granulomatous skin condition that can present with a variety of cutaneous morphologies. It is characterized by collagen degeneration, mucin deposition, and palisaded or interstitial histiocytes. Although the mechanism underlying development of GA is unknown, studies point to a cell-mediated hypersensitivity reaction to an as-yet undetermined antigen. Systemic associations with diabetes, thyroid disorders, lipid abnormalities, malignancy, and infection are described in atypical GA. Treatment is divided into localized skin-directed therapies and systemic immunomodulatory or immunosuppressive therapies. The selected treatment modality should be based on disease severity, comorbid conditions, consideration of potential side effects, and patient preference. PMID:26143416
Butsch, F; Weidenthaler-Barth, B; von Stebut, E
2015-11-01
Granuloma annulare is a benign, chronic inflammatory skin disease. Its pathogenesis is still unclear, but reports on infections as a trigger can be found. In addition, some authors reported an association with other systemic disease, e.g., cancer, trauma, and diabetes mellitus; however, these have not been verified. The clinical picture of granuloma annulare ranges from the localized form predominantly at the extremities to disseminated, subcutaneous, or perforating forms. Diagnosis is based on the typical clinical presentation which may be confirmed by a biopsy. Histologically, necrobiotic areas within granulomatous inflammation are typical. The prognosis of the disease is good with spontaneous resolution being frequently observed, especially in localized forms. Disseminated manifestations tend to persist longer, and recurrences are reported. When choosing between different therapeutic options, the benign disease character versus the individual degree of suffering and the potential therapy side effects must be considered. For local treatment, topical application of corticosteroids is most common. Disseminated forms can be treated systemically with corticosteroids for several weeks; alternatively, dapsone, hydroxychloroquine, retinoids, fumaric acid, cyclosporine, and anti-TNFα appear to be effective. PMID:26487494
Supercement for Annular Seal and Long-Term Integrity in Deep, Hot Wells "DeepTrek"
CSI Technologies
2007-08-31
The purpose of this project is to formulate a 'Supercement' designed for improving the long-term sealing integrity in HPHT wells. Phase I concentrated on chemistry studies and screening tests to design and evaluate Portland-based, hybrid Portland, and non-Portland-based cement systems suitable for further scale-up testing. Phase II work concentrated on additional lab and field testing to reduce the candidate materials list to two systems, as well as scaleup activities aimed at verifying performance at the field scale. Phase II was extended thorough a proposal to develop additional testing capabilities aimed at quantifying cementing material properties and performance that were previously not possible. Phase III focused on bringing the material(s) developed in previous Phases to commercialization, through Field Trials, Cost/Benefit Analysis, and Technology Transfer. Extensive development and testing work throughout the project led to Phase III commercialization of two very different materials: (1) Highly-expansive cement (Portland-based), patent pending as 'PRESTRESSED CEMENT'; and (2) Epoxy Resin (non-Portland-based), patent pending. Trade name is Ultra Seal-R. In Phase III, work concentrated on application of the Supercement materials in various increasingly-challenging wells. Previous testing revealed that PRESTRESSED CEMENT, when applied in weak or unconsolidated formations, tends to expand away from the central pipe, restricting the applicability of this material to competent formations. Tests were devised to quantify this effect so the material could be applied in appropriate wells. Additionally, the testing was needed because of industry resistance to expansive cements, due to previous marketing attempts with other materials that were less than successful. Field trials with the Epoxy Resin currently numbers in the hundreds of jobs at up to 295 deg F, with a large percentage being completely successful. Both the PRESTRESSED CEMENT as well as the Ultra Seal
Supercement for Annular Seal and Long-Term Integrity in Deep, Hot Wells "Deep Trek"
Kevin D. Edgley; Fred L. Sabins; Larry T. Watters
2005-08-31
The purpose of this project is to formulate a ''Supercement'' designed for improving the long-term sealing integrity in HPHT wells. Phase I concentrated on chemistry studies and screening tests to design and evaluate Portland-based, hybrid Portland, and non-Portland-based cement systems suitable for further scale-up testing. Phase II work concentrated on additional lab and field testing to reduce the candidate materials list to two systems, as well as scale up activities aimed at verifying performance at the field scale. Phase II was extended thorough a proposal to develop additional testing capabilities aimed at quantifying cementing material properties and performance that were previously not possible. Two materials are being taken into Phase III for field testing and commercialization: {lg_bullet} Highly-expansive cement (Portland-based), patent pending as ''Pre-Stressed Cement'' {lg_bullet} Epoxy Resin (non-Portland-based), patent pending In Phase II, significant effort was expended on scaling up the processes for handling resin in the field, as it is quite different than conventional Portland-based cements in mixing, personnel protection, and cleanup. Through this effort, over fifty (50) field jobs were done at a variety of temperatures and depths, most with excellent results. Large-scale field testing was less relevant with Pre-stressed Cement, because the materials and surface processes do not vary from those that have been developed for conventional Portland materials over the last eighty (80) years. The formulation is quite unique, however, and performs very differently than conventional Portland cements downhole.
Superposition State Molecular Dynamics.
Venkatnathan, Arun; Voth, Gregory A
2005-01-01
The ergodic sampling of rough energy landscapes is crucial for understanding phenomena like protein folding, peptide aggregation, polymer dynamics, and the glass transition. These rough energy landscapes are characterized by the presence of many local minima separated by high energy barriers, where Molecular Dynamics (MD) fails to satisfy ergodicity. To enhance ergodic behavior, we have developed the Superposition State Molecular Dynamics (SSMD) method, which uses a superposition of energy states to obtain an effective potential for the MD simulation. In turn, the dynamics on this effective potential can be used to sample the configurational free energy of the real potential. The effectiveness of the SSMD method for a one-dimensional rough potential energy landscape is presented as a test case. PMID:26641113
Artificial neural superposition eye.
Brückner, Andreas; Duparré, Jacques; Dannberg, Peter; Bräuer, Andreas; Tünnermann, Andreas
2007-09-17
We propose an ultra-thin imaging system which is based on the neural superposition compound eye of insects. Multiple light sensitive pixels in the footprint of each lenslet of this multi-channel configuration enable the parallel imaging of the individual object points. Together with the digital superposition of related signals this multiple sampling enables advanced functionalities for artificial compound eyes. Using this technique, color imaging and a circumvention for the trade-off between resolution and sensitivity of ultra-compact camera devices have been demonstrated in this article. The optical design and layout of such a system is discussed in detail. Experimental results are shown which indicate the attractiveness of microoptical artificial compound eyes for applications in the field of machine vision, surveillance or automotive imaging. PMID:19547555
Yu, Chang-shui; Yi, X. X.; Song, He-shan
2007-02-15
Bounds on the concurrence of the superposition state in terms of the concurrences of the states being superposed are found in this paper. The bounds on concurrence are quite different from those on the entanglement measured by von Neumann entropy [Linden et al., Phys. Rev. Lett. 97, 100502 (2006)]. In particular, a nonzero lower bound can be provided if the states being superposed are properly constrained.
Robust mesoscopic superposition of strongly correlated ultracold atoms
Hallwood, David W.; Ernst, Thomas; Brand, Joachim
2010-12-15
We propose a scheme to create coherent superpositions of annular flow of strongly interacting bosonic atoms in a one-dimensional ring trap. The nonrotating ground state is coupled to a vortex state with mesoscopic angular momentum by means of a narrow potential barrier and an applied phase that originates from either rotation or a synthetic magnetic field. We show that superposition states in the Tonks-Girardeau regime are robust against single-particle loss due to the effects of strong correlations. The coupling between the mesoscopically distinct states scales much more favorably with particle number than in schemes relying on weak interactions, thus making particle numbers of hundreds or thousands feasible. Coherent oscillations induced by time variation of parameters may serve as a 'smoking gun' signature for detecting superposition states.
Reconfigurable mosaic annular arrays.
Thomenius, Kai E; Wodnicki, Robert; Cogan, Scott D; Fisher, Rayette A; Burdick, Bill; Smith, L Scott; Khuri-Yakub, Pierre; Lin, Der-Song; Zhuang, Xuefeng; Bonitz, Barry; Davies, Todd; Thomas, Glen; Woychik, Charles
2014-07-01
Mosaic annular arrays (MAA) based on reconfigurable array (RA) transducer electronics assemblies are presented as a potential solution for future highly integrated ultrasonic transducer subsystems. Advantages of MAAs include excellent beam quality and depth of field resulting from superior elevational focus compared with 1-D electronically scanned arrays, as well as potentially reduced cost, size, and power consumption resulting from the use of a limited number of beamforming channels for processing a large number of subelements. Specific design tradeoffs for these highly integrated arrays are discussed in terms of array specifications for center frequency, element pitch, and electronic switch-on resistance. Large-area RAs essentially function as RC delay lines. Efficient architectures which take into account RC delay effects are presented. Architectures for integration of the transducer and electronics layers of large-area array implementations are reviewed. PMID:24960699
Subcutaneous granuloma annulare.
Requena, Luis; Fernández-Figueras, María Teresa
2007-06-01
Subcutaneous granuloma annulare is a rare clinicopathologic variant of granuloma annulare, characterized by subcutaneous nodules that may appear alone or in association with intradermal lesions. The pathogenesis of this deep variant of granuloma annulare remains uncertain. Subcutaneous granuloma annulare appears more frequently in children and young adults, and the lesions consist of subcutaneous nodules with no inflammatory appearance at the skin surface, most commonly located on the anterior aspects of the lower legs, hands, head, and buttocks. Usually, subcutaneous granuloma annulare is an authentic and exclusive panniculitic process with no dermal participation, although in 25% of the patients lesions of subcutaneous granuloma annulare coexist with the classic findings of granuloma annulare in the dermis. Histopathologically, subcutaneous granuloma annulare consist of areas of basophilic degeneration of collagen bundles with peripheral palisading granulomas involving the connective tissue septa of the subcutis. Usually, the area of necrobiosis in subcutaneous granuloma annulare is larger than in the dermal counterpart. The central necrobiotic areas contain increased amounts of connective tissue mucin and nuclear dust from neutrophils between the degenerated collagen bundles. Eosinophils are more common in subcutaneous granuloma annulare than in the dermal counterpart. There are not descriptions of subcutaneous granuloma annulare showing a histopathologic pattern of the so-called incomplete or interstitial variant. Histopathologic differential diagnosis of subcutaneous granuloma annulare includes rheumatoid nodule, necrobiosis lipoidica and epithelioid sarcoma. PMID:17544961
Superposition of Polytropes in the Inner Heliosheath
NASA Astrophysics Data System (ADS)
Livadiotis, G.
2016-03-01
This paper presents a possible generalization of the equation of state and Bernoulli's integral when a superposition of polytropic processes applies in space and astrophysical plasmas. The theory of polytropic thermodynamic processes for a fixed polytropic index is extended for a superposition of polytropic indices. In general, the superposition may be described by any distribution of polytropic indices, but emphasis is placed on a Gaussian distribution. The polytropic density-temperature relation has been used in numerous analyses of space plasma data. This linear relation on a log-log scale is now generalized to a concave-downward parabola that is able to describe the observations better. The model of the Gaussian superposition of polytropes is successfully applied in the proton plasma of the inner heliosheath. The estimated mean polytropic index is near zero, indicating the dominance of isobaric thermodynamic processes in the sheath, similar to other previously published analyses. By computing Bernoulli's integral and applying its conservation along the equator of the inner heliosheath, the magnetic field in the inner heliosheath is estimated, B ˜ 2.29 ± 0.16 μG. The constructed normalized histogram of the values of the magnetic field is similar to that derived from a different method that uses the concept of large-scale quantization, bringing incredible insights to this novel theory.
Reexamination of entanglement of superpositions
NASA Astrophysics Data System (ADS)
Gour, Gilad
2007-11-01
We find tight lower and upper bounds on the entanglement of a superposition of two bipartite states in terms of the entanglement of the two states constituting the superposition. Our upper bound is dramatically tighter than the one presented by Linden [Phys. Rev. Lett. 97, 100502 (2006)] and our lower bound can be used to provide lower bounds on different measures of entanglement such as the entanglement of formation and the entanglement of subspaces. We also find that in the case in which the two states are one-sided orthogonal, the entanglement of the superposition state can be expressed explicitly in terms of the entanglement of the two states in the superposition.
Superposition Enhanced Nested Sampling
NASA Astrophysics Data System (ADS)
Martiniani, Stefano; Stevenson, Jacob D.; Wales, David J.; Frenkel, Daan
2014-07-01
The theoretical analysis of many problems in physics, astronomy, and applied mathematics requires an efficient numerical exploration of multimodal parameter spaces that exhibit broken ergodicity. Monte Carlo methods are widely used to deal with these classes of problems, but such simulations suffer from a ubiquitous sampling problem: The probability of sampling a particular state is proportional to its entropic weight. Devising an algorithm capable of sampling efficiently the full phase space is a long-standing problem. Here, we report a new hybrid method for the exploration of multimodal parameter spaces exhibiting broken ergodicity. Superposition enhanced nested sampling combines the strengths of global optimization with the unbiased or athermal sampling of nested sampling, greatly enhancing its efficiency with no additional parameters. We report extensive tests of this new approach for atomic clusters that are known to have energy landscapes for which conventional sampling schemes suffer from broken ergodicity. We also introduce a novel parallelization algorithm for nested sampling.
Superpositions of Free Electron Vortices and Measurement of Matter Wave Gouy Phase
NASA Astrophysics Data System (ADS)
McMorran, Benjamin; Harvey, Tyler; Pierce, Jordan; Linck, Martin
2014-03-01
We demonstrate superpositions of free electron matter wave orbital states using nanofabricated diffraction holograms. The orbital superposition is comprised of an electron beam that is a coherent mixture of two overlapped, co-propagating vortex beam modes with different topological charge. Whereas a pure mode electron vortex beam forms an annular spot when projected onto an imaging detector, the superposition has an intensity profile that is broken into azimuthal lobes. The number of lobes is given by the absolute difference in topological charge between the two orbital components. We created superpositions of vortices with various topological charges, from ml = 0 to 15. We use these superposition states to measure the Gouy phase measurement for matter waves. We discuss the possibility of using these beams to measure magnetic fields. Support from University of Oregon CAMCOR, and LBNL LDRD grant.
Quantum superpositions of crystalline structures
Baltrusch, Jens D.; Morigi, Giovanna; Cormick, Cecilia; De Chiara, Gabriele; Calarco, Tommaso
2011-12-15
A procedure is discussed for creating coherent superpositions of motional states of ion strings. The motional states are across the structural transition linear-zigzag, and their coherent superposition is achieved by means of spin-dependent forces, such that a coherent superposition of the electronic states of one ion evolves into an entangled state between the chain's internal and external degrees of freedom. It is shown that the creation of such an entangled state can be revealed by performing Ramsey interferometry with one ion of the chain.
Network Class Superposition Analyses
Pearson, Carl A. B.; Zeng, Chen; Simha, Rahul
2013-01-01
Networks are often used to understand a whole system by modeling the interactions among its pieces. Examples include biomolecules in a cell interacting to provide some primary function, or species in an environment forming a stable community. However, these interactions are often unknown; instead, the pieces' dynamic states are known, and network structure must be inferred. Because observed function may be explained by many different networks (e.g., for the yeast cell cycle process [1]), considering dynamics beyond this primary function means picking a single network or suitable sample: measuring over all networks exhibiting the primary function is computationally infeasible. We circumvent that obstacle by calculating the network class ensemble. We represent the ensemble by a stochastic matrix , which is a transition-by-transition superposition of the system dynamics for each member of the class. We present concrete results for derived from Boolean time series dynamics on networks obeying the Strong Inhibition rule, by applying to several traditional questions about network dynamics. We show that the distribution of the number of point attractors can be accurately estimated with . We show how to generate Derrida plots based on . We show that -based Shannon entropy outperforms other methods at selecting experiments to further narrow the network structure. We also outline an experimental test of predictions based on . We motivate all of these results in terms of a popular molecular biology Boolean network model for the yeast cell cycle, but the methods and analyses we introduce are general. We conclude with open questions for , for example, application to other models, computational considerations when scaling up to larger systems, and other potential analyses. PMID:23565141
Reexamination of entanglement of superpositions
Gour, Gilad
2007-11-15
We find tight lower and upper bounds on the entanglement of a superposition of two bipartite states in terms of the entanglement of the two states constituting the superposition. Our upper bound is dramatically tighter than the one presented by Linden et al. [Phys. Rev. Lett. 97, 100502 (2006)] and our lower bound can be used to provide lower bounds on different measures of entanglement such as the entanglement of formation and the entanglement of subspaces. We also find that in the case in which the two states are one-sided orthogonal, the entanglement of the superposition state can be expressed explicitly in terms of the entanglement of the two states in the superposition.
Behavior interrelationships in annular flow
NASA Astrophysics Data System (ADS)
Schubring, Duwayne
Two-phase gas-liquid flow occurs in many types of industrial boiling and condensing heat transfer equipment, including the reactor cores of boiling water nuclear reactors (BWRs) and the steam generators of pressurized water reactors (PWRs). In annular flow, the liquid phase often travels as both a thin film around the wall (containing disturbance waves and base film) and as entrained droplets in the central gas core. Gas bubbles are also often entrained into this film. Annular flow displays several quantifiable flow behaviors, including pressure loss, disturbance waves, and film thickness, along with micro-scale velocity profiles and fluctuations in the liquid film. The conventional approach to annular flow closely links film thickness and pressure loss, but relies on an assumed film velocity profile and does not consider disturbance waves explicitly. The present work seeks to explore a more complete range of behaviors in both horizontal and vertical flow to explore the relationships among them and thereby improve modeling of annular flow. Several of these investigations employ quantitative visualization. Modern optics and computing (in the form of non-trivial data reduction codes) are applied to the study of two-phase flow to process images of a physical experiment to quantify behavior information. Quantitative visualization allows for rapid acquisition of a large volume of flow behavior data, which allows for analysis of the flow behaviors themselves and how they relate to one another and to global modeling. By integrating behavior data from these quantitative visualizations and other conventional experimental investigations, a new two-region (base film and disturbance wave) model is proposed that can be implemented given only flow rates, external geometry, and fluid properties.
Annular pancreas is an abnormal ring or collar of pancreatic tissue that encircles the duodenum (the part of the ... intestine that connects to stomach). This portion of pancreas can constrict the duodenum and block or impair ...
Mechanically expandable annular seal
Gilmore, Richard F.
1983-01-01
A mechanically expandable annular reusable seal assembly to form an annular hermetic barrier between two stationary, parallel, and planar containment surfaces. A rotatable ring, attached to the first surface, has ring wedges resembling the saw-tooth array of a hole saw. Matching seal wedges are slidably attached to the ring wedges and have their motion restricted to be perpendicular to the second surface. Each seal wedge has a face parallel to the second surface. An annular elastomer seal has a central annular region attached to the seal wedges' parallel faces and has its inner and outer circumferences attached to the first surface. A rotation of the ring extends the elastomer seal's central region perpendicularly towards the second surface to create the fluidtight barrier. A counterrotation removes the barrier.
Mechanically expandable annular seal
Gilmore, R.F.
1983-07-19
A mechanically expandable annular reusable seal assembly to form an annular hermetic barrier between two stationary, parallel, and planar containment surfaces is described. A rotatable ring, attached to the first surface, has ring wedges resembling the saw-tooth array of a hole saw. Matching seal wedges are slidably attached to the ring wedges and have their motion restricted to be perpendicular to the second surface. Each seal wedge has a face parallel to the second surface. An annular elastomer seal has a central annular region attached to the seal wedges' parallel faces and has its inner and outer circumferences attached to the first surface. A rotation of the ring extends the elastomer seal's central region perpendicularly towards the second surface to create the fluid tight barrier. A counter rotation removes the barrier. 6 figs.
Erythematous Granuloma Annulare
Jang, Eun Joo; Lee, Ji Yeoun; Kim, Mi Kyeong
2011-01-01
Granuloma annulare (GA) is a common, benign, chronic inflammatory disorder, which is characterized by grouped papules in an enlarging annular shape. It has been described in several clinical subtypes, including localized, generalized, subcutaneous, perforating, and erythematous types. Even though generalized, subcutaneous, and perforating types of GA are unusual, there are several reports of those types. However, erythematous or patch GA, has not been reported yet in the Korean literature. Herein, we report a 42-year-old woman with pruritic erythematous patches, which occurred on the extremities without preceding event, and showed typical clinical and histopatologic findings of erythematous GA. PMID:21909221
Linear superposition in nonlinear equations.
Khare, Avinash; Sukhatme, Uday
2002-06-17
Several nonlinear systems such as the Korteweg-de Vries (KdV) and modified KdV equations and lambda phi(4) theory possess periodic traveling wave solutions involving Jacobi elliptic functions. We show that suitable linear combinations of these known periodic solutions yield many additional solutions with different periods and velocities. This linear superposition procedure works by virtue of some remarkable new identities involving elliptic functions. PMID:12059300
Campoamor-Stursberg, R.
2014-04-15
It is shown that for any α,β∈R and k∈Z, the Hamiltonian H{sub k}=p{sub 1}p{sub 2}−αq{sub 2}{sup (2k+1)}q{sub 1}{sup (−2k−3)}−(β)/2 q{sub 2}{sup k}q{sub 1}{sup (−k−2)} is super-integrable, possessing fundamental constants of motion of degrees 2 and 2k + 2 in the momenta.
On the superposition principle in interference experiments
Sinha, Aninda; H. Vijay, Aravind; Sinha, Urbasi
2015-01-01
The superposition principle is usually incorrectly applied in interference experiments. This has recently been investigated through numerics based on Finite Difference Time Domain (FDTD) methods as well as the Feynman path integral formalism. In the current work, we have derived an analytic formula for the Sorkin parameter which can be used to determine the deviation from the application of the principle. We have found excellent agreement between the analytic distribution and those that have been earlier estimated by numerical integration as well as resource intensive FDTD simulations. The analytic handle would be useful for comparing theory with future experiments. It is applicable both to physics based on classical wave equations as well as the non-relativistic Schrödinger equation. PMID:25973948
Eccentric annular crack under general nonuniform internal pressure
NASA Astrophysics Data System (ADS)
Moeini-Ardakani, S.; Kamali, M. T.; Shodja, H. M.
2016-08-01
For a better approximation of ring-shaped and toroidal cracks, a new eccentric annular crack model is proposed and an analytical approach for determination of the corresponding stress intensity factors is given. The crack is subjected to arbitrary mode I loading. A rigorous solution is provided by mapping the eccentric annular crack to a concentric annular crack. The analysis leads to two decoupled Fredholm integral equations of the second kind. For the sake of verification, the problem of a conventional annular crack is examined. Furthermore, for various crack configurations of an eccentric annular crack under uniform tension, the stress intensity factors pertaining to the inner and outer crack edges are delineated in dimensionless plots.
The Paraconsistent Logic of Quantum Superpositions
NASA Astrophysics Data System (ADS)
da Costa, N.; de Ronde, C.
2013-07-01
Physical superpositions exist both in classical and in quantum physics. However, what is exactly meant by `superposition' in each case is extremely different. In this paper we discuss some of the multiple interpretations which exist in the literature regarding superpositions in quantum mechanics. We argue that all these interpretations have something in common: they all attempt to avoid `contradiction'. We argue in this paper, in favor of the importance of developing a new interpretation of superpositions which takes into account contradiction, as a key element of the formal structure of the theory, "right from the start". In order to show the feasibility of our interpretational project we present an outline of a paraconsistent approach to quantum superpositions which attempts to account for the contradictory properties present in general within quantum superpositions. This approach must not be understood as a closed formal and conceptual scheme but rather as a first step towards a different type of understanding regarding quantum superpositions.
Reider, Samuel B.
1979-01-01
An industrial gas turbine engine includes an inclined annular combustor made up of a plurality of support segments each including inner and outer walls of trapezoidally configured planar configuration extents and including side flanges thereon interconnected by means of air cooled connector bolt assemblies to form a continuous annular combustion chamber therebetween and wherein an air fuel mixing chamber is formed at one end of the support segments including means for directing and mixing fuel within a plenum and a perforated header plate for directing streams of air and fuel mixture into the combustion chamber; each of the outer and inner walls of each of the support segments having a ribbed lattice with tracks slidably supporting porous laminated replaceable panels and including pores therein for distributing combustion air into the combustion chamber while cooling the inner surface of each of the panels by transpiration cooling thereof.
Granuloma annulare, patch type.
Victor, Frank C; Mengden, Stephanie
2008-01-01
A 64-year-old man was referred to the Bellevue Hospital Center Dermatology Clinic for evaluation of an asymptomatic eruption on his left inner arm, which had been present for 4 months and was unresponsive to topical anti-fungal therapy. One month after the initial eruption, 2 similar, asymptomatic lesions appeared on the right inner arm. The lesions were slowly expanding. A biopsy specimen from the left medial arm was consistent with interstitial granuloma annulare. The patient's clinical presentation was consistent with patch-type granuloma annulare. He was treated with a mid-potency topical glucocorticoid twice daily for 4 weeks without benefit. Since the eruption was asymptomatic, treatment was discontinued. PMID:18627757
Creating a Superposition of Unknown Quantum States.
Oszmaniec, Michał; Grudka, Andrzej; Horodecki, Michał; Wójcik, Antoni
2016-03-18
The superposition principle is one of the landmarks of quantum mechanics. The importance of quantum superpositions provokes questions about the limitations that quantum mechanics itself imposes on the possibility of their generation. In this work, we systematically study the problem of the creation of superpositions of unknown quantum states. First, we prove a no-go theorem that forbids the existence of a universal probabilistic quantum protocol producing a superposition of two unknown quantum states. Second, we provide an explicit probabilistic protocol generating a superposition of two unknown states, each having a fixed overlap with the known referential pure state. The protocol can be applied to generate coherent superposition of results of independent runs of subroutines in a quantum computer. Moreover, in the context of quantum optics it can be used to efficiently generate highly nonclassical states or non-Gaussian states. PMID:27035290
Creating a Superposition of Unknown Quantum States
NASA Astrophysics Data System (ADS)
Oszmaniec, Michał; Grudka, Andrzej; Horodecki, Michał; Wójcik, Antoni
2016-03-01
The superposition principle is one of the landmarks of quantum mechanics. The importance of quantum superpositions provokes questions about the limitations that quantum mechanics itself imposes on the possibility of their generation. In this work, we systematically study the problem of the creation of superpositions of unknown quantum states. First, we prove a no-go theorem that forbids the existence of a universal probabilistic quantum protocol producing a superposition of two unknown quantum states. Second, we provide an explicit probabilistic protocol generating a superposition of two unknown states, each having a fixed overlap with the known referential pure state. The protocol can be applied to generate coherent superposition of results of independent runs of subroutines in a quantum computer. Moreover, in the context of quantum optics it can be used to efficiently generate highly nonclassical states or non-Gaussian states.
Mesoscopic Superposition States in Relativistic Landau Levels
Bermudez, A.; Martin-Delgado, M. A.; Solano, E.
2007-09-21
We show that a linear superposition of mesoscopic states in relativistic Landau levels can be built when an external magnetic field couples to a relativistic spin 1/2 charged particle. Under suitable initial conditions, the associated Dirac equation produces unitarily superpositions of coherent states involving the particle orbital quanta in a well-defined mesoscopic regime. We demonstrate that these mesoscopic superpositions have a purely relativistic origin and disappear in the nonrelativistic limit.
Rotational superposition: a review of methods.
Flower, D R
1999-01-01
Rotational superposition is one of the most commonly used algorithms in molecular modelling. Many different methods of solving superposition have been suggested. Of these, methods based on the quaternion parameterization of rotation are fast, accurate, and robust. Quaternion parameterization-based methods cannot result in rotation inversion and do not have special cases such as co-linearity or co-planarity of points. Thus, quaternion parameterization-based methods are the best choice for rotational superposition applications. PMID:10736782
Superposition flows of entangled polymeric solutions
NASA Astrophysics Data System (ADS)
Ianniruberto, Giovanni; Unidad, Herwin Jerome
2015-12-01
Parallel and orthogonal superposition experiments by Vermant et al. (1998) on a polydisperse, entangled polymeric solution are here analyzed by using a simple, multi-mode differential constitutive equation based on the tube model, and also accounting for convective constraint release effects. Model predictions are in very good qualitative and quantitative agreement with parallel superposition data, while some discrepancies are found with orthogonal data, thus suggesting that orthogonal superposition experiments represent a more severe test for molecularly-based constitutive equations.
Macroscopic optomechanical superposition via periodic qubit flipping
NASA Astrophysics Data System (ADS)
Ge, Wenchao; Zubairy, M. Suhail
2015-01-01
We propose a scheme to generate macroscopic superpositions of well-distinguishable coherent states in an optomechanical system via periodic qubit flipping. Our scheme does not require the single-photon strong-coupling rate of an optomechanical system. The generated mechanical superposition state can be reconstructed using mechanical quantum-state reconstruction. The proposed scheme relies on recycling of an atom, fast atomic qubit flipping, and coherent state mapping between a single-photon superposition state and an atomic superposition state. We discuss the experimental feasibility of our proposal under current technology.
Kang, Yungmo
2005-10-04
An annular heat recuperator is formed with alternating hot and cold cells to separate counter-flowing hot and cold fluid streams. Each cold cell has a fluid inlet formed in the inner diameter of the recuperator near one axial end, and a fluid outlet formed in the outer diameter of the recuperator near the other axial end to evenly distribute fluid mass flow throughout the cell. Cold cells may be joined with the outlet of one cell fluidly connected to the inlet of an adjacent downstream cell to form multi-stage cells.
The M&M Superposition Principle.
ERIC Educational Resources Information Center
Miller, John B.
2000-01-01
Describes a physical system for demonstrating operators, eigenvalues, and superposition of states for a set of unusual wave functions. Uses candy to provide students with a visual and concrete picture of a superposition of states rather than an abstract plot of several overlaid mathematical states. (WRM)
Harnoss, Jonathan M.; Harnoss, Julian C.; Diener, Markus K.; Contin, Pietro; Ulrich, Alexis B.; Büchler, Markus W.; Schmitz-Winnenthal, Friedrich H.
2014-01-01
Abstract Portal annular pancreas (PAP) is an asymptomatic congenital pancreas anomaly, in which portal and/or mesenteric veins are encased by pancreas tissue. The aim of the study was to determine the role of PAP in pancreatic surgery as well as its management and potential complication, specifically, postoperative pancreatic fistula (POPF). On the basis of a case report, the MEDLINE and ISI Web of Science databases were systematically reviewed up to September 2012. All articles describing a case of PAP were considered. In summary, 21 studies with 59 cases were included. The overall prevalence of PAP was 2.4% and the patients' mean (SD) age was 55.9 (16.2) years. The POPF rate in patients with PAP (12 pancreaticoduodenectomies and 3 distal pancreatectomies) was 46.7% (in accordance with the definition of the International Study Group of Pancreatic Surgery). Portal annular pancreas is a quite unattended pancreatic variant with high prevalence and therefore still remains a clinical challenge to avoid postoperative complications. To decrease the risk for POPF, attentive preoperative diagnostics should also focus on PAP. In pancreaticoduodenectomy, a shift of the resection plane to the pancreas tail should be considered; in extensive pancreatectomy, coverage of the pancreatic remnant by the falciform ligament could be a treatment option. PMID:25207658
Axisymmetric annular curtain stability
NASA Astrophysics Data System (ADS)
Ahmed, Zahir U.; Khayat, Roger E.; Maissa, Philippe; Mathis, Christian
2012-06-01
A temporal stability analysis was carried out to investigate the stability of an axially moving viscous annular liquid jet subject to axisymmetric disturbances in surrounding co-flowing viscous gas media. We investigated in this study the effects of inertia, surface tension, the gas-to-liquid density ratio, the inner-to-outer radius ratio and the gas-to-liquid viscosity ratio on the stability of the jet. With an increase in inertia, the growth rate of the unstable disturbances is found to increase. The dominant (or most unstable) wavenumber decreases with increasing Reynolds number for larger values of the gas-to-liquid viscosity ratio. However, an opposite tendency for the most unstable wavenumber is predicted for small viscosity ratio in the same inertia range. The surrounding gas density, in the presence of viscosity, always reduces the growth rate, hence stabilizing the flow. There exists a critical value of the density ratio above which the flow becomes stable for very small viscosity ratio, whereas for large viscosity ratio, no stable flow appears in the same range of the density ratio. The curvature has a significant destabilizing effect on the thin annular jet, whereas for a relatively thick jet, the maximum growth rate decreases as the inner radius increases, irrespective of the surrounding gas viscosity. The degree of instability increases with Weber number for a relatively large viscosity ratio. In contrast, for small viscosity ratio, the growth rate exhibits a dramatic dependence on the surface tension. There is a small Weber number range, which depends on the viscosity ratio, where the flow is stable. The viscosity ratio always stabilizes the flow. However, the dominant wavenumber increases with increasing viscosity ratio. The range of unstable wavenumbers is affected only by the curvature effect.
Concomitant occurrence of patch granuloma annulare and classical granuloma annulare.
Tsuruta, Daisuke; Sowa, Junko; Hiroyasu, Sho; Ishii, Masamitsu; Kobayashi, Hiromi
2011-05-01
Granuloma annulare (GA) is characterized clinically as annularly-distributed, erythematous papules on the extremities in children and adolescents. GA is recognized histologically as palisading granulomas with central degenerated collagen and mucin deposits. Here, we present a case of concomitant occurrence of patch GA (PGA), the most rare type of GA, and classical GA in a patient. A 60-year-old man was referred to our hospital for asymptomatic eruptions on the upper arms, forearms, right flank and right lateral chest. Clinical examination revealed annular erythematous plaques composed of numerous small papules on bilateral upper arms and forearms. Moreover, an indurative, exudative erythematous to violaceous plaque was present on the right lateral chest and right flank. Histopathology of the former was compatible with palisade-type GA, and the latter interstitial-type GA. This is the first report of PGA concomitant with "classical" annular papular lesions. PMID:21352310
Depth-targeted transvascular drug delivery by using annular-shaped photomechanical waves
NASA Astrophysics Data System (ADS)
Akiyama, Takuya; Sato, Shunichi; Ashida, Hiroshi; Terakawa, Mitsuhiro
2011-02-01
Laser-based drug delivery is attractive for the targeting capability due to high spatial controllability of laser energy. Recently, we found that photomechanical waves (PMWs) can transiently increase the permeability of blood vessels in skin, muscle and brain of rats. In this study, we examined the use of annular-shaped PMWs to increase pressure at target depths due to superposition effect of pressure waves. This can increase the permeability of blood vessels located in the specific depth regions, enabling depth-targeted transvascular drug delivery. Annular PMWs were produced by irradiating a laser-absorbing material with annular-shaped pulsed laser beams that were produced by using an axicon lens. We first examined propagation and pressure characteristics of annular PMWs in tissue phantoms and confirmed an increased pressure at a target depth, which can be controlled by changing laser parameters. We injected Evans blue (EB) into a rat tail vein, and annular PMWs (inner diameter, 3 mm; outer diameter, 5 mm) were applied from the myofascial surface of the anterior tibialis muscle. After perfusion fixation, we observed fluorescence originating from EB in the tissue. We observed intense fluorescence at a target depth region of around 5 mm. These results demonstrate the capability of annular PMWs for depth-targeted transvascular drug delivery.
Engineering mesoscopic superpositions of superfluid flow
Hallwood, D. W.; Brand, J.
2011-10-15
Modeling strongly correlated atoms demonstrates the possibility to prepare quantum superpositions that are robust against experimental imperfections and temperature. Such superpositions of vortex states are formed by adiabatic manipulation of interacting ultracold atoms confined to a one-dimensional ring trapping potential when stirred by a barrier. Here, we discuss the influence of nonideal experimental procedures and finite temperature. Adiabaticity conditions for changing the stirring rate reveal that superpositions of many atoms are most easily accessed in the strongly interacting, Tonks-Girardeau, regime, which is also the most robust at finite temperature. NOON-type superpositions of weakly interacting atoms are most easily created by adiabatically decreasing the interaction strength by means of a Feshbach resonance. The quantum dynamics of small numbers of particles is simulated and the size of the superpositions is calculated based on their ability to make precision measurements. The experimental creation of strongly correlated and NOON-type superpositions with about 100 atoms seems feasible in the near future.
Manufacture of annular cermet articles
Forsberg, Charles W.; Sikka, Vinod K.
2004-11-02
A method to produce annular-shaped, metal-clad cermet components directly produces the form and avoids multiple fabrication steps such as rolling and welding. The method includes the steps of: providing an annular hollow form with inner and outer side walls; filling the form with a particulate mixture of ceramic and metal; closing, evacuating, and hermetically sealing the form; heating the form to an appropriate temperature; and applying force to consolidate the particulate mixture into solid cermet.
Experimental superposition of orders of quantum gates.
Procopio, Lorenzo M; Moqanaki, Amir; Araújo, Mateus; Costa, Fabio; Alonso Calafell, Irati; Dowd, Emma G; Hamel, Deny R; Rozema, Lee A; Brukner, Časlav; Walther, Philip
2015-01-01
Quantum computers achieve a speed-up by placing quantum bits (qubits) in superpositions of different states. However, it has recently been appreciated that quantum mechanics also allows one to 'superimpose different operations'. Furthermore, it has been shown that using a qubit to coherently control the gate order allows one to accomplish a task--determining if two gates commute or anti-commute--with fewer gate uses than any known quantum algorithm. Here we experimentally demonstrate this advantage, in a photonic context, using a second qubit to control the order in which two gates are applied to a first qubit. We create the required superposition of gate orders by using additional degrees of freedom of the photons encoding our qubits. The new resource we exploit can be interpreted as a superposition of causal orders, and could allow quantum algorithms to be implemented with an efficiency unlikely to be achieved on a fixed-gate-order quantum computer. PMID:26250107
An approximate CPHD filter for superpositional sensors
NASA Astrophysics Data System (ADS)
Mahler, Ronald; El-Fallah, Adel
2012-06-01
Most multitarget tracking algorithms, such as JPDA, MHT, and the PHD and CPHD filters, presume the following measurement model: (a) targets are point targets, (b) every target generates at most a single measurement, and (c) any measurement is generated by at most a single target. However, the most familiar sensors, such as surveillance and imaging radars, violate assumption (c). This is because they are actually superpositional-that is, any measurement is a sum of signals generated by all of the targets in the scene. At this conference in 2009, the first author derived exact formulas for PHD and CPHD filters that presume general superpositional measurement models. Unfortunately, these formulas are computationally intractable. In this paper, we modify and generalize a Gaussian approximation technique due to Thouin, Nannuru, and Coates to derive a computationally tractable superpositional-CPHD filter. Implementation requires sequential Monte Carlo (particle filter) techniques.
Real-time dose computation: GPU-accelerated source modeling and superposition/convolution
Jacques, Robert; Wong, John; Taylor, Russell; McNutt, Todd
2011-01-15
Purpose: To accelerate dose calculation to interactive rates using highly parallel graphics processing units (GPUs). Methods: The authors have extended their prior work in GPU-accelerated superposition/convolution with a modern dual-source model and have enhanced performance. The primary source algorithm supports both focused leaf ends and asymmetric rounded leaf ends. The extra-focal algorithm uses a discretized, isotropic area source and models multileaf collimator leaf height effects. The spectral and attenuation effects of static beam modifiers were integrated into each source's spectral function. The authors introduce the concepts of arc superposition and delta superposition. Arc superposition utilizes separate angular sampling for the total energy released per unit mass (TERMA) and superposition computations to increase accuracy and performance. Delta superposition allows single beamlet changes to be computed efficiently. The authors extended their concept of multi-resolution superposition to include kernel tilting. Multi-resolution superposition approximates solid angle ray-tracing, improving performance and scalability with a minor loss in accuracy. Superposition/convolution was implemented using the inverse cumulative-cumulative kernel and exact radiological path ray-tracing. The accuracy analyses were performed using multiple kernel ray samplings, both with and without kernel tilting and multi-resolution superposition. Results: Source model performance was <9 ms (data dependent) for a high resolution (400{sup 2}) field using an NVIDIA (Santa Clara, CA) GeForce GTX 280. Computation of the physically correct multispectral TERMA attenuation was improved by a material centric approach, which increased performance by over 80%. Superposition performance was improved by {approx}24% to 0.058 and 0.94 s for 64{sup 3} and 128{sup 3} water phantoms; a speed-up of 101-144x over the highly optimized Pinnacle{sup 3} (Philips, Madison, WI) implementation. Pinnacle{sup 3
Macroscopic Quantum Superposition in Cavity Optomechanics.
Liao, Jie-Qiao; Tian, Lin
2016-04-22
Quantum superposition in mechanical systems is not only key evidence for macroscopic quantum coherence, but can also be utilized in modern quantum technology. Here we propose an efficient approach for creating macroscopically distinct mechanical superposition states in a two-mode optomechanical system. Photon hopping between the two cavity modes is modulated sinusoidally. The modulated photon tunneling enables an ultrastrong radiation-pressure force acting on the mechanical resonator, and hence significantly increases the mechanical displacement induced by a single photon. We study systematically the generation of the Yurke-Stoler-like states in the presence of system dissipations. We also discuss the experimental implementation of this scheme. PMID:27152802
Macroscopic Quantum Superposition in Cavity Optomechanics
NASA Astrophysics Data System (ADS)
Liao, Jie-Qiao; Tian, Lin
2016-04-01
Quantum superposition in mechanical systems is not only key evidence for macroscopic quantum coherence, but can also be utilized in modern quantum technology. Here we propose an efficient approach for creating macroscopically distinct mechanical superposition states in a two-mode optomechanical system. Photon hopping between the two cavity modes is modulated sinusoidally. The modulated photon tunneling enables an ultrastrong radiation-pressure force acting on the mechanical resonator, and hence significantly increases the mechanical displacement induced by a single photon. We study systematically the generation of the Yurke-Stoler-like states in the presence of system dissipations. We also discuss the experimental implementation of this scheme.
Large energy superpositions via Rydberg dressing
NASA Astrophysics Data System (ADS)
Khazali, Mohammadsadegh; Lau, Hon Wai; Humeniuk, Adam; Simon, Christoph
2016-08-01
We propose to create superposition states of over 100 strontium atoms in a ground state or metastable optical clock state using the Kerr-type interaction due to Rydberg state dressing in an optical lattice. The two components of the superposition can differ by an order of 300 eV in energy, allowing tests of energy decoherence models with greatly improved sensitivity. We take into account the effects of higher-order nonlinearities, spatial inhomogeneity of the interaction, decay from the Rydberg state, collective many-body decoherence, atomic motion, molecular formation, and diminishing Rydberg level separation for increasing principal number.
Annular Eclipse as Seen by Hinode
This timelapse shows an annular eclipse as seen by JAXA's Hinode satellite on Jan. 4, 2011. An annular eclipse occurs when the moon, slightly more distant from Earth than on average, moves directly...
The principle of superposition in human prehension
Zatsiorsky, Vladimir M.; Latash, Mark L.; Gao, Fan; Shim, Jae Kun
2010-01-01
SUMMARY The experimental evidence supports the validity of the principle of superposition for multi-finger prehension in humans. Forces and moments of individual digits are defined by two independent commands: “Grasp the object stronger/weaker to prevent slipping” and “Maintain the rotational equilibrium of the object”. The effects of the two commands are summed up. PMID:20186284
The Evolution and Development of Neural Superposition
Agi, Egemen; Langen, Marion; Altschuler, Steven J.; Wu, Lani F.; Zimmermann, Timo
2014-01-01
Visual systems have a rich history as model systems for the discovery and understanding of basic principles underlying neuronal connectivity. The compound eyes of insects consist of up to thousands of small unit eyes that are connected by photoreceptor axons to set up a visual map in the brain. The photoreceptor axon terminals thereby represent neighboring points seen in the environment in neighboring synaptic units in the brain. Neural superposition is a special case of such a wiring principle, where photoreceptors from different unit eyes that receive the same input converge upon the same synaptic units in the brain. This wiring principle is remarkable, because each photoreceptor in a single unit eye receives different input and each individual axon, among thousands others in the brain, must be sorted together with those few axons that have the same input. Key aspects of neural superposition have been described as early as 1907. Since then neuroscientists, evolutionary and developmental biologists have been fascinated by how such a complicated wiring principle could evolve, how it is genetically encoded, and how it is developmentally realized. In this review article, we will discuss current ideas about the evolutionary origin and developmental program of neural superposition. Our goal is to identify in what way the special case of neural superposition can help us answer more general questions about the evolution and development of genetically “hard-wired” synaptic connectivity in the brain. PMID:24912630
Eosinophilic annular erythema in childhood - Case report.
Abarzúa, Alvaro; Giesen, Laura; Silva, Sergio; González, Sergio
2016-01-01
Eosinophilic annular erythema is a rare, benign, recurrent disease, clinically characterized by persistent, annular, erythematous lesions, revealing histopathologically perivascular infiltrates with abundant eosinophils. This report describes an unusual case of eosinophilic annular erythema in a 3-year-old female, requiring sustained doses of hydroxychloroquine to be adequately controlled. PMID:27579748
Eosinophilic annular erythema in childhood - Case report*
Abarzúa, Alvaro; Giesen, Laura; Silva, Sergio; González, Sergio
2016-01-01
Eosinophilic annular erythema is a rare, benign, recurrent disease, clinically characterized by persistent, annular, erythematous lesions, revealing histopathologically perivascular infiltrates with abundant eosinophils. This report describes an unusual case of eosinophilic annular erythema in a 3-year-old female, requiring sustained doses of hydroxychloroquine to be adequately controlled. PMID:27579748
NASA Technical Reports Server (NTRS)
Palazzolo, Alan B.; Venkataraman, Balaji; Padavala, Sathya S.; Ryan, Steve; Vallely, Pat; Funston, Kerry
1996-01-01
This paper highlights the accomplishments on a joint effort between NASA - Marshall Space Flight Center and Texas A and M University to develop accurate seal analysis software for use in rocket turbopump design, design audits and trouble shooting. Results for arbitrary clearance profile, transient simulation, thermal effects solution and flexible seal wall model are presented. A new solution for eccentric seals based on cubic spline interpolation and ordinary differential equation integration is also presented.
An experimental investigation of straight and curved annular wall jets
NASA Technical Reports Server (NTRS)
Rodman, L. C.; Wood, N. J.; Roberts, L.
1987-01-01
Accurate turbulence measurements taken in wall jet flows are difficult to obtain, due to high intensity turbulence and problems in achieving two-dimensionality. The problem is compounded when streamwise curvature of the flow is introduced, since the jet entrainment and turbulence levels are greatly increased over the equivalent planar values. In this experiment, two-dimensional straight and curved incompressible wall jet flows are simulated by having a jet blow axially over a cylinder. Hot wire measurements and some Laser Doppler Velocimetry measurements are presented for straight and curved wall jet flows. The results for the straight wall showed good agreement between the annular flow data and the rectangular data taken by previous researchers. For the jets with streamwise curvature, there was agreement between the annular and corresponding rectangular jets for the flow region closest to the slot exit. An integral analysis was used as a simple technique to interpret the experimental results. Integral momentum calculations were performed for both straight and curved annular and two dimensional wall jets. The results of the calculation were used to identify transverse curvature parameters and to predict the values of those parameters which would delineate the region where the annular flow can satisfactorily simulate two dimensional flow.
Macroscopic Quantum Superposition in Cavity Optomechanics
NASA Astrophysics Data System (ADS)
Liao, Jie-Qiao; Tian, Lin
Quantum superposition in mechanical systems is not only a key evidence of macroscopic quantum coherence, but can also be utilized in modern quantum technology. Here we propose an efficient approach for creating macroscopically distinct mechanical superposition states in a two-mode optomechanical system. Photon hopping between the two cavity-modes is modulated sinusoidally. The modulated photon tunneling enables an ultrastrong radiation-pressure force acting on the mechanical resonator, and hence significantly increases the mechanical displacement induced by a single photon. We present systematic studies on the generation of the Yurke-Stoler-like states in the presence of system dissipations. The state generation method is general and it can be implemented with either optomechanical or electromechanical systems. The authors are supported by the National Science Foundation under Award No. NSF-DMR-0956064 and the DARPA ORCHID program through AFOSR.
Concurrence of superpositions of many states
Akhtarshenas, Seyed Javad
2011-04-15
In this paper, we use the concurrence vector as a measure of entanglement, and investigate lower and upper bounds on the concurrence of a superposition of bipartite states as a function of the concurrence of the superposed states. We show that the amount of entanglement quantified by the concurrence vector is exactly the same as that quantified by I concurrence, so that our results can be compared to those given in Phys. Rev. A 76, 042328 (2007). We obtain a tighter lower bound in the case in which the two superposed states are orthogonal. We also show that when the two superposed states are not necessarily orthogonal, both lower and upper bounds are, in general, tighter than the bounds given in terms of the I concurrence. An extension of the results to the case with more than two states in the superpositions is also given.
Theory of low voltage annular beam free-electron lasers
Blank, M.; Freund, H.P.; Jackson, R.H.
1995-12-31
An nonlinear analysis of an annular beam propagating through a cylindrical waveguide in the presence of a helical wiggler and an axial guide field is presented. The analysis is based upon the ARACHNE simulation which is a non-wiggler-averaged slow-time-scale simulation code in which the electromagnetic field is represented as a superposition of the TE and TM modes in a vacuum waveguide, and the beam space-charge waves are represented as a superposition of Gould-Trivelpiece modes. The DC self-electric and self-magnetic fields are also included in the model. ARACHNE has been extensively benchmarked against experiments at MIT and NRL in the past with good agreement, but all of these experiments have dealt with solid electron beams and beam voltages in excess of 200 kV. In seeking to reduce the beam voltage requirements we now consider the effect of operation with an annular beam. One advantage to be obtained by using an annular beam is that, for a fixed beam current, the effect of the DC selffields (i.e., the space-charge depression in beam voltage) will be reduced relative to that of a solid beam. This facilitates beam transport in short period wigglers in which the transverse dimensions are also small. A specific example is under study which makes use of 55 kV/5A electron beam with inner and outer radii of 0.27 cm and 0.33 cm respectively. The wiggler amplitude is 250 G with a period of 0.9 cm. and guide fields up to 3 kG corresponding to Group I trajectories. The waveguide radius is chosen to correspond to grazing incidence for the fundamental mode in Ku-Band (12-18 GHz). Preliminary results indicate that efficiencies upwards of 10% are possible with no wiggler taper. In addition, the energy spread must be held below 0.1%, and the instantaneous bandwidth is found to be greater than 20%.
Annular arc accelerator shock tube
NASA Technical Reports Server (NTRS)
Leibowitz, L. P. (Inventor)
1976-01-01
An annular arc accelerator shock tube employs a cold gas driver to flow a stream of gas from an expansion section through a high voltage electrode section to a test section, thus driving a shock wave in front of it. A glow discharge detects the shock wave and actuates a trigger generator which in turn fires spark-gap switches to discharge a bank of capacitors across a centered cathode and an annular anode in tandem electrode sections. The initial shock wave passes through the anode section from the cathode section thereby depositing energy into the flow gas without the necessity of any diaphragm opening in the gas flow from the expansion section through the electrode sections.
Toward quantum superposition of living organisms
NASA Astrophysics Data System (ADS)
Romero-Isart, Oriol; Juan, Mathieu L.; Quidant, Romain; Cirac, J. Ignacio
2010-03-01
The most striking feature of quantum mechanics is the existence of superposition states, where an object appears to be in different situations at the same time. The existence of such states has been previously tested with small objects, such as atoms, ions, electrons and photons (Zoller et al 2005 Eur. Phys. J. D 36 203-28), and even with molecules (Arndt et al 1999 Nature 401 680-2). More recently, it has been shown that it is possible to create superpositions of collections of photons (Deléglise et al 2008 Nature 455 510-14), atoms (Hammerer et al 2008 arXiv:0807.3358) or Cooper pairs (Friedman et al 2000 Nature 406 43-6). Very recent progress in optomechanical systems may soon allow us to create superpositions of even larger objects, such as micro-sized mirrors or cantilevers (Marshall et al 2003 Phys. Rev. Lett. 91 130401; Kippenberg and Vahala 2008 Science 321 1172-6 Marquardt and Girvin 2009 Physics 2 40; Favero and Karrai 2009 Nature Photon. 3 201-5), and thus to test quantum mechanical phenomena at larger scales. Here we propose a method to cool down and create quantum superpositions of the motion of sub-wavelength, arbitrarily shaped dielectric objects trapped inside a high-finesse cavity at a very low pressure. Our method is ideally suited for the smallest living organisms, such as viruses, which survive under low-vacuum pressures (Rothschild and Mancinelli 2001 Nature 406 1092-101) and optically behave as dielectric objects (Ashkin and Dziedzic 1987 Science 235 1517-20). This opens up the possibility of testing the quantum nature of living organisms by creating quantum superposition states in very much the same spirit as the original Schrödinger's cat 'gedanken' paradigm (Schrödinger 1935 Naturwissenschaften 23 807-12, 823-8, 844-9). We anticipate that our paper will be a starting point for experimentally addressing fundamental questions, such as the role of life and consciousness in quantum mechanics.
Energy Focusability of Annular Beams
NASA Astrophysics Data System (ADS)
Astadjov, Dimo N.
2010-01-01
A simulation of coherent annular flat two-level beams by two-dimensional Fast Fourier Transform is presented. After parameterization of the source beam (the `input') we examined the influence of its parameters on the shape and proportions of the output beam profile. The output pattern has a prominent central peak and faint rings concentrically surrounding it. The fraction of the central peak energy to the whole energy of beam, PF0 gives a notion of energy spread within the focal spot: PF0 is a function of beam annularity, k (i.e. `inside diameter/outside diameter' ratio) and the intensity dip, Idip of annulus central area (i.e. ring intensity minus central-bottom intensity, normalized). Up to k = 0.8 and Idip = 0.75, PF0 does not change too much—it is ⩾0.7 which is ⩾90% of PF0 maximum (0.778 at k = 0 and Idip = 0). Simulations revealed that even great changes in the shape of input beam annulus lead to small variations in the energy spread of output beam profile in the range of practical use of coherent annular beams.
X-ray optics simulation using Gaussian superposition technique.
Idir, Mourad; Cywiak, Moisés; Morales, Arquímedes; Modi, Mohammed H
2011-09-26
We present an efficient method to perform x-ray optics simulation with high or partially coherent x-ray sources using Gaussian superposition technique. In a previous paper, we have demonstrated that full characterization of optical systems, diffractive and geometric, is possible by using the Fresnel Gaussian Shape Invariant (FGSI) previously reported in the literature. The complex amplitude distribution in the object plane is represented by a linear superposition of complex Gaussians wavelets and then propagated through the optical system by means of the referred Gaussian invariant. This allows ray tracing through the optical system and at the same time allows calculating with high precision the complex wave-amplitude distribution at any plane of observation. This technique can be applied in a wide spectral range where the Fresnel diffraction integral applies including visible, x-rays, acoustic waves, etc. We describe the technique and include some computer simulations as illustrative examples for x-ray optical component. We show also that this method can be used to study partial or total coherence illumination problem. PMID:21996845
Time-Temperature Superposition Applied to PBX Mechanical Properties
NASA Astrophysics Data System (ADS)
Thompson, Darla; Deluca, Racci
2011-06-01
The use of plastic-bonded explosives (PBXs) in weapon applications requires a certain level of structural/mechanical integrity. Uniaxial tension and compression experiments characterize the mechanical response of materials over a wide range of temperatures and strain rates, providing the basis for predictive modeling in more complex geometries. After years of data collection on a wide variety of PBX formulations, we have applied time-temperature superposition principles to a mechanical properties database which includes PBX 9501, PBX 9502, PBXN-110, PBXN-9, and HPP (propellant). The results of quasi-static tension and compression, SHPB compression, and cantilever DMA are compared. Time-temperature relationships of maximum stress and corresponding strain values are analyzed in addition to the more conventional analysis of modulus. Our analysis shows adherence to the principles of time-temperature superposition and correlations of mechanical response to the binder glass transition and specimen density. Direct ties relate time-temperature analysis to the underlying basis of existing PBX mechanical models (ViscoSCRAM). Results suggest that, within limits, mechanical response can be predicted at conditions not explicitly measured. LA-UR 11-01096.
Time-temperature superposition applied to PBX mechanical properties
NASA Astrophysics Data System (ADS)
Thompson, Darla; DeLuca, Racci; Wright, Walter J.
2012-03-01
The use of plastic-bonded explosives (PBXs) in weapon applications requires that they possess and maintain a level of structural/mechanical integrity. Uniaxial tension and compression experiments are typically used to characterize the mechanical response of materials over a wide range of temperatures and strain rates, providing the basis for predictive modeling in more complex geometries. After many years of data collection on a variety of PBX formulations, we have here applied the principles of time-temperature superposition to a mechanical properties database which includes PBX 9501, PBX 9502, PBXN-110, PBXN-9, and HPP (propellant). Consistencies are demonstrated between the results of quasi-static tension and compression, dynamic Split-Hopkinson Pressure Bar (SHPB) compression, and cantilever Dynamic Mechanical Analysis (DMA). Timetemperature relationships of maximum stress and corresponding strain values are analyzed, in addition to the more conventional analysis of modulus. The extensive analysis shows adherence to the principles of time-temperature superposition and correlations of mechanical response to binder glasstransition temperature (Tg) and specimen density. Direct ties exist between the time-temperature analysis and the underlying basis of a useful existing PBX mechanical model (ViscoSCRAM). Results give confidence that, with some limitations, mechanical response can be predicted at conditions not explicitly measured.
X-ray optics simulation using Gaussian superposition technique
Idir, M.; Cywiak, M.; Morales, A. and Modi, M.H.
2011-09-15
We present an efficient method to perform x-ray optics simulation with high or partially coherent x-ray sources using Gaussian superposition technique. In a previous paper, we have demonstrated that full characterization of optical systems, diffractive and geometric, is possible by using the Fresnel Gaussian Shape Invariant (FGSI) previously reported in the literature. The complex amplitude distribution in the object plane is represented by a linear superposition of complex Gaussians wavelets and then propagated through the optical system by means of the referred Gaussian invariant. This allows ray tracing through the optical system and at the same time allows calculating with high precision the complex wave-amplitude distribution at any plane of observation. This technique can be applied in a wide spectral range where the Fresnel diffraction integral applies including visible, x-rays, acoustic waves, etc. We describe the technique and include some computer simulations as illustrative examples for x-ray optical component. We show also that this method can be used to study partial or total coherence illumination problem.
Annular beam shaping and optical trepanning
NASA Astrophysics Data System (ADS)
Zeng, Danyong
surfaces of the annulus, respectively, and full Gaussian with maximum intensity within the annulus. Two refractive arrangements have been presented in this study. Geometric optics, or ray optics, describes light propagation in terms of rays. However, it is a simplification of optics, and fails to account for many important optical effects such as diffraction and polarization. The diffractive behaviors of this optical trepanning system are stimulated and analyzed based on the Fresnel diffraction integral. Diffraction patterns of the resulting optical system are measured using a laser beam analyzer and compared with the theoretical results. Based on the theoretical and experimental results, the effects of experimental parameters are discussed. We have designed the annular beam shaping optical elements and the gas delivery system to construct an optical trepanning system. Laser drilling experiments are performed on the Stainless Steel-316 (SS 316) plate and the Inconel 718 (IN 718) plate. The geometry of the trepanning holes with different sizes is presented in this study.
Granuloma annulare in herpes zoster scars.
Ohata, C; Shirabe, H; Takagi, K; Kawatsu, T
2000-03-01
A 54-year-old Japanese female developed granuloma annulare twice in herpes zoster scars. Soon after the second event, she developed ulcerative colitis, which was well controlled by sulfonamides and corticosteroid suppository. She had no history of diabetes mellitus. There was no recurrence of granuloma annulare by June of 1999. Granuloma annulare might have contributed to the complications of ulcerative colitis, although this had not been noticed before. PMID:10774142
Annular Solar Eclipse of 10 May 1994
NASA Technical Reports Server (NTRS)
Espenak, Fred; Anderson, Jay
1993-01-01
An annular eclipse of the Sun will be widely visible from the Western Hemisphere on 10 May 1994. The path of the Moon's shadow passes through Mexico, the United States of America, maritime Canada, the North Atlantic, the Azores and Morocco. Detailed predictions for this event are presented and include tables of geographic coordinates of the annular path, local circumstances for hundreds of cities, maps of the path of annular and partial eclipse, weather prospects, and the lunar limb profile.
Maximum predictive power and the superposition principle
NASA Technical Reports Server (NTRS)
Summhammer, Johann
1994-01-01
In quantum physics the direct observables are probabilities of events. We ask how observed probabilities must be combined to achieve what we call maximum predictive power. According to this concept the accuracy of a prediction must only depend on the number of runs whose data serve as input for the prediction. We transform each probability to an associated variable whose uncertainty interval depends only on the amount of data and strictly decreases with it. We find that for a probability which is a function of two other probabilities maximum predictive power is achieved when linearly summing their associated variables and transforming back to a probability. This recovers the quantum mechanical superposition principle.
Atom Microscopy via Dual Resonant Superposition
NASA Astrophysics Data System (ADS)
Abdul Jabar, M. S.; Bakht, Amin Bacha; Jalaluddin, M.; Iftikhar, Ahmad
2015-12-01
An M-type Rb87 atomic system is proposed for one-dimensional atom microscopy under the condition of Electromagnetically Induced Transparency. Super-localization of the atom in the absorption spectrum while its delocalization in the dispersion spectrum is observed due to the dual superposition effect of the resonant fields. The observed minimum uncertainty peaks will find important applications in Laser cooling, creating focused atom beams, atom nanolithography, and in measurement of the center-of-mass wave function of moving atoms.
Design of artificial spherical superposition compound eye
NASA Astrophysics Data System (ADS)
Cao, Zhaolou; Zhai, Chunjie; Wang, Keyi
2015-12-01
In this research, design of artificial spherical superposition compound eye is presented. The imaging system consists of three layers of lens arrays. In each channel, two lenses are designed to control the angular magnification and a field lens is added to improve the image quality and extend the field of view. Aspherical surfaces are introduced to improve the image quality. Ray tracing results demonstrate that the light from the same object point is focused at the same imaging point through different channels. Therefore the system has much higher energy efficiency than conventional spherical apposition compound eye.
On Kolmogorov's superpositions and Boolean functions
Beiu, V.
1998-12-31
The paper overviews results dealing with the approximation capabilities of neural networks, as well as bounds on the size of threshold gate circuits. Based on an explicit numerical (i.e., constructive) algorithm for Kolmogorov's superpositions they will show that for obtaining minimum size neutral networks for implementing any Boolean function, the activation function of the neurons is the identity function. Because classical AND-OR implementations, as well as threshold gate implementations require exponential size (in the worst case), it will follow that size-optimal solutions for implementing arbitrary Boolean functions require analog circuitry. Conclusions and several comments on the required precision are ending the paper.
Annular MHD Physics for Turbojet Energy Bypass
NASA Technical Reports Server (NTRS)
Schneider, Steven J.
2011-01-01
The use of annular Hall type MHD generator/accelerator ducts for turbojet energy bypass is evaluated assuming weakly ionized flows obtained from pulsed nanosecond discharges. The equations for a 1-D, axisymmetric MHD generator/accelerator are derived and numerically integrated to determine the generator/accelerator performance characteristics. The concept offers a shockless means of interacting with high speed inlet flows and potentially offers variable inlet geometry performance without the complexity of moving parts simply by varying the generator loading parameter. The cycle analysis conducted iteratively with a spike inlet and turbojet flying at M = 7 at 30 km altitude is estimated to have a positive thrust per unit mass flow of 185 N-s/kg. The turbojet allowable combustor temperature is set at an aggressive 2200 deg K. The annular MHD Hall generator/accelerator is L = 3 m in length with a B(sub r) = 5 Tesla magnetic field and a conductivity of sigma = 5 mho/m for the generator and sigma= 1.0 mho/m for the accelerator. The calculated isentropic efficiency for the generator is eta(sub sg) = 84 percent at an enthalpy extraction ratio, eta(sub Ng) = 0.63. The calculated isentropic efficiency for the accelerator is eta(sub sa) = 81 percent at an enthalpy addition ratio, eta(sub Na) = 0.62. An assessment of the ionization fraction necessary to achieve a conductivity of sigma = 1.0 mho/m is n(sub e)/n = 1.90 X 10(exp -6), and for sigma = 5.0 mho/m is n(sub e)/n = 9.52 X 10(exp -6).
Confocal Annular Josephson Tunnel Junctions
NASA Astrophysics Data System (ADS)
Monaco, Roberto
2016-04-01
The physics of Josephson tunnel junctions drastically depends on their geometrical configurations and here we show that also tiny geometrical details play a determinant role. More specifically, we develop the theory of short and long annular Josephson tunnel junctions delimited by two confocal ellipses. The behavior of a circular annular Josephson tunnel junction is then seen to be simply a special case of the above result. For junctions having a normalized perimeter less than one, the threshold curves in the presence of an in-plane magnetic field of arbitrary orientations are derived and computed even in the case with trapped Josephson vortices. For longer junctions, a numerical analysis is carried out after the derivation of the appropriate motion equation for the Josephson phase. We found that the system is modeled by a modified and perturbed sine-Gordon equation with a space-dependent effective Josephson penetration length inversely proportional to the local junction width. Both the fluxon statics and dynamics are deeply affected by the non-uniform annulus width. Static zero-field multiple-fluxon solutions exist even in the presence of a large bias current. The tangential velocity of a traveling fluxon is not determined by the balance between the driving and drag forces due to the dissipative losses. Furthermore, the fluxon motion is characterized by a strong radial inward acceleration which causes electromagnetic radiation concentrated at the ellipse equatorial points.
Confocal Annular Josephson Tunnel Junctions
NASA Astrophysics Data System (ADS)
Monaco, Roberto
2016-09-01
The physics of Josephson tunnel junctions drastically depends on their geometrical configurations and here we show that also tiny geometrical details play a determinant role. More specifically, we develop the theory of short and long annular Josephson tunnel junctions delimited by two confocal ellipses. The behavior of a circular annular Josephson tunnel junction is then seen to be simply a special case of the above result. For junctions having a normalized perimeter less than one, the threshold curves in the presence of an in-plane magnetic field of arbitrary orientations are derived and computed even in the case with trapped Josephson vortices. For longer junctions, a numerical analysis is carried out after the derivation of the appropriate motion equation for the Josephson phase. We found that the system is modeled by a modified and perturbed sine-Gordon equation with a space-dependent effective Josephson penetration length inversely proportional to the local junction width. Both the fluxon statics and dynamics are deeply affected by the non-uniform annulus width. Static zero-field multiple-fluxon solutions exist even in the presence of a large bias current. The tangential velocity of a traveling fluxon is not determined by the balance between the driving and drag forces due to the dissipative losses. Furthermore, the fluxon motion is characterized by a strong radial inward acceleration which causes electromagnetic radiation concentrated at the ellipse equatorial points.
Bistability and hysteresis of annular impinging jets
NASA Astrophysics Data System (ADS)
Tisovsky, Tomas
2016-06-01
In present study, the bistability and hysteresis of annular impinging jets is investigated. Annular impinging jets are simulated using open source CFD code - OpenFOAM. Both flow field patterns of interest are obtained and hysteresis is found by means of dynamic mesh simulation. Effect of nozzle exit velocity on resulting hysteresis loop is also illustrated.
Phase properties of multicomponent superposition states in various amplifiers
NASA Technical Reports Server (NTRS)
Lee, Kang-Soo; Kim, M. S.
1994-01-01
There have been theoretical studies for generation of optical coherent superposition states. Once the superposition state is generated it is natural to ask if it is possible to amplify it without losing the nonclassical properties of the field state. We consider amplification of the superposition state in various amplifiers such as a sub-Poissonian amplifier, a phase-sensitive amplifier and a classical amplifier. We show the evolution of phase probability distribution functions in the amplifier.
Granuloma annulare with prominent lymphoid infiltrates ("pseudolymphomatous" granuloma annulare).
Cota, Carlo; Ferrara, Gerardo; Cerroni, Lorenzo
2012-05-01
Granuloma annulare (GA) is characterized histopathologically by 3 patterns: necrobiotic granuloma, interstitial incomplete form and, rarely, sarcoidal or tuberculoid granuloma. The amount of lymphoid infiltrate in GA is usually limited. We describe 10 cases of GA with prominent "pseudolymphomatous" lymphoid infiltrates mimicking cutaneous lymphoid hyperplasia. Patients were 6 males and 4 females (mean age 49.9 years, median age 47 years, age range 25-70). Lesions were localized to a limited area of the body (n = 6), or involved the entire trunk (n = 3), or were generalized (n = 1). The correct clinical diagnosis of GA was provided only in 30% of the cases. In all cases, histopathologic features were characterized by dense, nodular, superficial, and deep infiltrates of lymphocytes. Immunohistology revealed predominance of T lymphocytes in 7 of 7 tested cases. This "pseudolymphomatous" variant of GA represents a pitfall in the histopathologic diagnosis of the disease and may be misinterpreted as other types of cutaneous lymphoproliferative disorders. PMID:22207445
Authentication Protocol using Quantum Superposition States
Kanamori, Yoshito; Yoo, Seong-Moo; Gregory, Don A.; Sheldon, Frederick T
2009-01-01
When it became known that quantum computers could break the RSA (named for its creators - Rivest, Shamir, and Adleman) encryption algorithm within a polynomial-time, quantum cryptography began to be actively studied. Other classical cryptographic algorithms are only secure when malicious users do not have sufficient computational power to break security within a practical amount of time. Recently, many quantum authentication protocols sharing quantum entangled particles between communicators have been proposed, providing unconditional security. An issue caused by sharing quantum entangled particles is that it may not be simple to apply these protocols to authenticate a specific user in a group of many users. An authentication protocol using quantum superposition states instead of quantum entangled particles is proposed. The random number shared between a sender and a receiver can be used for classical encryption after the authentication has succeeded. The proposed protocol can be implemented with the current technologies we introduce in this paper.
Means of manufacturing annular arrays
Day, R.A.
1985-10-10
A method is described for manufacturing an annular acoustic transducer array from a plate of transducer material, which enables production of precision aligned arrays at low cost. The circular plate is sawed along at least two lines that are radial to the axis of the plate. At steps along each radial cut, the plate is rotated first in one direction and then in an opposite direction by a predetermined angle such as slightly less than 90/sup 0/. The cuts result in the forming of several largely ring-shaped lands, each largely ring-shaped land being joined to the other rings of different radii by thin portions of the plate, and each ring being cut into segments. The bridges that join different rings hold the transducer together until it can be mounted on a lens.
Nonclassical Properties of Q-Deformed Superposition Light Field State
NASA Technical Reports Server (NTRS)
Ren, Min; Shenggui, Wang; Ma, Aiqun; Jiang, Zhuohong
1996-01-01
In this paper, the squeezing effect, the bunching effect and the anti-bunching effect of the superposition light field state which involving q-deformation vacuum state and q-Glauber coherent state are studied, the controllable q-parameter of the squeezing effect, the bunching effect and the anti-bunching effect of q-deformed superposition light field state are obtained.
Sealing arrangement with annular flexible disc
Pennell, William E.; Honigsberg, Charles A.
1983-01-01
Fluid sealing arrangements including an annular shaped flexible disc having enlarged edges disposed within channel-shaped annular receptacles which are spaced from one another. The receptacles form an annular region for contacting and containing the enlarged edges of the disc, and the disc is preloaded to a conical configuration. The disc is flexibly and movably supported within the receptacles so that unevenly distributed relative motion between the components containing the receptacles is accommodated without loss of sealing contact between the edges of the disc and the walls of the receptacles.
Etizolam-induced superficial erythema annulare centrifugum.
Kuroda, K; Yabunami, H; Hisanaga, Y
2002-01-01
Erythema annulare centrifugum (EAC) is characterized by slowly enlarging annular erythematous lesions. Although the origin is not clear in most cases, EAC has been associated with infections, medications, and in rare cases, underlying malignancy. We describe a patient who developed annular erythematous lesions after etizolam administration. The eruptions were typical of the superficial form of EAC, both clinically and histopathologically. The lesions disappeared shortly after discontinuation of the medication. Patch testing with etizolam gave positive results. To our knowledge this is the first reported case of etizolam-induced superficial EAC. PMID:11952667
Xiao, Qingsheng; Klitis, Charalambos; Li, Shimao; Chen, Yueyang; Cai, Xinlun; Sorel, Marc; Yu, Siyuan
2016-02-22
An integrated approach to produce photonic orbital angular momentum (OAM) superposition states with arbitrary OAM spectrum has been demonstrated. Superposition states between two vector OAM modes have been achieved by integrating a superimposed angular grating in one silicon micro-ring resonator, with each mode having near equal weight. The topological charge difference between the two compositional OAM modes is determined by the difference between the numbers of elements in the two original gratings being superimposed, while the absolute values of the topological charge can be changed synchronously by switching WGM resonant wavelengths. This novel approach provides a scalable and flexible source for the OAM-based quantum information and optical manipulation applications. PMID:26906981
Method and apparatus for continuous annular electrochromatography
Scott, Charles D.
1987-01-01
Separation of complex mixtures and solutions can be carried out using a method and apparatus for continuous annular electrochromatography. Solutes are diverted radially by an imposed electrical field as they move downward in a rotating chromatographic column.
Granuloma Annulare Treated with Excimer Laser
Ragi, Jennifer; Milgraum, Sandy
2012-01-01
Objective: To review the current therapy for granuloma annulare and report a case of refractory generalized granuloma annulare successfully treated with excimer laser. A discussion about the characteristics of excimer laser and the mechanism of its effectiveness is presented. Design: Patient case report and literature review. Setting: Outpatient dermatology practice. Participants: A 73-year-old woman suffering from generalized granuloma annulare for more than 40 years. Measurements: Change in clinical appearance of lesions. Results: Use of excimer laser therapy resulted in prompt and complete resolution in treated areas with no residual skin changes or side effects. Conclusion: Excimer laser therapy is a powerful treatment modality with minimal side effects for patients with granuloma annulare. Further study is necessary to elucidate optimal dosing, long-term efficacy, and safety profile. PMID:23198013
Annular-Cross-Section CFE Chamber
NASA Technical Reports Server (NTRS)
Sharnez, Rizwan; Sammons, David W.
1994-01-01
Proposed continuous-flow-electrophoresis (CFE) chamber of annular cross section offers advantages over conventional CFE chamber, and wedge-cross-section chamber described in "Increasing Sensitivity in Continuous-Flow Electrophoresis" (MFS-26176). In comparison with wedge-shaped chamber, chamber of annular cross section virtually eliminates such wall effects as electro-osmosis and transverse gradients of velocity. Sensitivity enhanced by incorporating gradient maker and radial (collateral) flow.
[Treatment of disseminated granuloma annulare with anthralin].
Jantke, M E; Bertsch, H-P; Schön, M P; Fuchs, T
2011-12-01
Granuloma annulare is a benign, often asymptomatic and self-limiting granulomatous skin disease. In cases of disseminated granuloma annulare, spontaneous regression is considerably less frequent than in localized forms so that therapy is often desired. Systemic treatments should always be assessed critically and reserved for patients who are severely affected and in whom treatment approaches with few side effects such as local application of anthralin do not suffice to achieve a satisfactory effect. PMID:21656108
Annular gel reactor for chemical pattern formation
Nosticzius, Zoltan; Horsthemke, Werner; McCormick, William D.; Swinney, Harry L.; Tam, Wing Y.
1990-01-01
The present invention is directed to an annular gel reactor suitable for the production and observation of spatiotemporal patterns created during a chemical reaction. The apparatus comprises a vessel having at least a first and second chamber separated one from the other by an annular polymer gel layer (or other fine porous medium) which is inert to the materials to be reacted but capable of allowing diffusion of the chemicals into it.
Adaptive optics scanning ophthalmoscopy with annular pupils
Sulai, Yusufu N.; Dubra, Alfredo
2012-01-01
Annular apodization of the illumination and/or imaging pupils of an adaptive optics scanning light ophthalmoscope (AOSLO) for improving transverse resolution was evaluated using three different normalized inner radii (0.26, 0.39 and 0.52). In vivo imaging of the human photoreceptor mosaic at 0.5 and 10° from fixation indicates that the use of an annular illumination pupil and a circular imaging pupil provides the most benefit of all configurations when using a one Airy disk diameter pinhole, in agreement with the paraxial confocal microscopy theory. Annular illumination pupils with 0.26 and 0.39 normalized inner radii performed best in terms of the narrowing of the autocorrelation central lobe (between 7 and 12%), and the increase in manual and automated photoreceptor counts (8 to 20% more cones and 11 to 29% more rods). It was observed that the use of annular pupils with large inner radii can result in multi-modal cone photoreceptor intensity profiles. The effect of the annular masks on the average photoreceptor intensity is consistent with the Stiles-Crawford effect (SCE). This indicates that combinations of images of the same photoreceptors with different apodization configurations and/or annular masks can be used to distinguish cones from rods, even when the former have complex multi-modal intensity profiles. In addition to narrowing the point spread function transversally, the use of annular apodizing masks also elongates it axially, a fact that can be used for extending the depth of focus of techniques such as adaptive optics optical coherence tomography (AOOCT). Finally, the positive results from this work suggest that annular pupil apodization could be used in refractive or catadioptric adaptive optics ophthalmoscopes to mitigate undesired back-reflections. PMID:22808435
Multiple Granuloma Annulare in a 2-year-old Child
Siddalingappa, Karjigi; Murthy, Sambasiviah Chidambara; Herakal, Kallappa; Kusuma, Marganahalli Ramachandra
2015-01-01
Granuloma annulare is a benign, self-limiting, inflammatory and granulomatous disease of unknown etiology occurring in both adults and children. An 18-month-old male child had multiple progressive annular plaques over the lower extremities. Clinical and histopathological features were consistent with granuloma annulare. Localized granuloma annulare is the most common form in children. We report a young child with multiple, progressive granuloma annulare over the lower extremities. PMID:26677301
Superposition rules for higher order systems and their applications
NASA Astrophysics Data System (ADS)
Cariñena, J. F.; Grabowski, J.; de Lucas, J.
2012-05-01
Superposition rules form a class of functions that describe general solutions of systems of first-order ordinary differential equations in terms of generic families of particular solutions and certain constants. In this work, we extend this notion and other related ones to systems of higher order differential equations and analyse their properties. Several results concerning the existence of various types of superposition rules for higher order systems are proved and illustrated with examples extracted from the physics and mathematics literature. In particular, two new superposition rules for the second- and third-order Kummer-Schwarz equations are derived.
Many-Body Basis Set Superposition Effect.
Ouyang, John F; Bettens, Ryan P A
2015-11-10
The basis set superposition effect (BSSE) arises in electronic structure calculations of molecular clusters when questions relating to interactions between monomers within the larger cluster are asked. The binding energy, or total energy, of the cluster may be broken down into many smaller subcluster calculations and the energies of these subsystems linearly combined to, hopefully, produce the desired quantity of interest. Unfortunately, BSSE can plague these smaller fragment calculations. In this work, we carefully examine the major sources of error associated with reproducing the binding energy and total energy of a molecular cluster. In order to do so, we decompose these energies in terms of a many-body expansion (MBE), where a "body" here refers to the monomers that make up the cluster. In our analysis, we found it necessary to introduce something we designate here as a many-ghost many-body expansion (MGMBE). The work presented here produces some surprising results, but perhaps the most significant of all is that BSSE effects up to the order of truncation in a MBE of the total energy cancel exactly. In the case of the binding energy, the only BSSE correction terms remaining arise from the removal of the one-body monomer total energies. Nevertheless, our earlier work indicated that BSSE effects continued to remain in the total energy of the cluster up to very high truncation order in the MBE. We show in this work that the vast majority of these high-order many-body effects arise from BSSE associated with the one-body monomer total energies. Also, we found that, remarkably, the complete basis set limit values for the three-body and four-body interactions differed very little from that at the MP2/aug-cc-pVDZ level for the respective subclusters embedded within a larger cluster. PMID:26574311
Nonclassical properties and quantum resources of hierarchical photonic superposition states
Volkoff, T. J.
2015-11-15
We motivate and introduce a class of “hierarchical” quantum superposition states of N coupled quantum oscillators. Unlike other well-known multimode photonic Schrödinger-cat states such as entangled coherent states, the hierarchical superposition states are characterized as two-branch superpositions of tensor products of single-mode Schrödinger-cat states. In addition to analyzing the photon statistics and quasiprobability distributions of prominent examples of these nonclassical states, we consider their usefulness for highprecision quantum metrology of nonlinear optical Hamiltonians and quantify their mode entanglement. We propose two methods for generating hierarchical superpositions in N = 2 coupled microwave cavities, exploiting currently existing quantum optical technology for generating entanglement between spatially separated electromagnetic field modes.
A Galois connection approach to superposition and inaccessibility
NASA Astrophysics Data System (ADS)
Butterfield, Jeremy; Melia, Joseph
1993-12-01
Working in a quantum logic framework and using the idea of Galois connections, we give a natural sufficient condition for superposition and inaccessibility to give the same closure map on sets of states.
Quantum State Engineering Via Coherent-State Superpositions
NASA Technical Reports Server (NTRS)
Janszky, Jozsef; Adam, P.; Szabo, S.; Domokos, P.
1996-01-01
The quantum interference between the two parts of the optical Schrodinger-cat state makes possible to construct a wide class of quantum states via discrete superpositions of coherent states. Even a small number of coherent states can approximate the given quantum states at a high accuracy when the distance between the coherent states is optimized, e. g. nearly perfect Fock state can be constructed by discrete superpositions of n + 1 coherent states lying in the vicinity of the vacuum state.
Optical threshold secret sharing scheme based on basic vector operations and coherence superposition
NASA Astrophysics Data System (ADS)
Deng, Xiaopeng; Wen, Wei; Mi, Xianwu; Long, Xuewen
2015-04-01
We propose, to our knowledge for the first time, a simple optical algorithm for secret image sharing with the (2,n) threshold scheme based on basic vector operations and coherence superposition. The secret image to be shared is firstly divided into n shadow images by use of basic vector operations. In the reconstruction stage, the secret image can be retrieved by recording the intensity of the coherence superposition of any two shadow images. Compared with the published encryption techniques which focus narrowly on information encryption, the proposed method can realize information encryption as well as secret sharing, which further ensures the safety and integrality of the secret information and prevents power from being kept centralized and abused. The feasibility and effectiveness of the proposed method are demonstrated by numerical results.
Annular feed air breathing fuel cell stack
Wilson, Mahlon S.
1996-01-01
A stack of polymer electrolyte fuel cells is formed from a plurality of unit cells where each unit cell includes fuel cell components defining a periphery and distributed along a common axis, where the fuel cell components include a polymer electrolyte membrane, an anode and a cathode contacting opposite sides of the membrane, and fuel and oxygen flow fields contacting the anode and the cathode, respectively, wherein the components define an annular region therethrough along the axis. A fuel distribution manifold within the annular region is connected to deliver fuel to the fuel flow field in each of the unit cells. In a particular embodiment, a single bolt through the annular region clamps the unit cells together. In another embodiment, separator plates between individual unit cells have an extended radial dimension to function as cooling fins for maintaining the operating temperature of the fuel cell stack.
Annular bilayer magnetoelectric composites: theoretical analysis.
Guo, Mingsen; Dong, Shuxiang
2010-01-01
The laminated bilayer magnetoelectric (ME) composites consist of magnetostrictive and piezoelectric layers are known to have giant ME coefficient due to the high coupling efficiency in bending mode. In our previous report, the bar-shaped bilayer composite has been investigated by using a magnetoelectric-coupling equivalent circuit. Here, we propose an annular bilayer ME composite, which consists of magnetostrictive and piezoelectric rings. This composite has a much lower resonance frequency of bending mode compared with its radial mode. In addition, the annular bilayer ME composite is expected to respond to vortex magnetic field as well as unidirectional magnetic field. In this paper, we investigate the annular bilayer ME composite by using impedance-matrix method and predict the ME coefficients as a function of geometric parameters of the composites. PMID:20178914
Quantum superposition at the half-metre scale.
Kovachy, T; Asenbaum, P; Overstreet, C; Donnelly, C A; Dickerson, S M; Sugarbaker, A; Hogan, J M; Kasevich, M A
2015-12-24
The quantum superposition principle allows massive particles to be delocalized over distant positions. Though quantum mechanics has proved adept at describing the microscopic world, quantum superposition runs counter to intuitive conceptions of reality and locality when extended to the macroscopic scale, as exemplified by the thought experiment of Schrödinger's cat. Matter-wave interferometers, which split and recombine wave packets in order to observe interference, provide a way to probe the superposition principle on macroscopic scales and explore the transition to classical physics. In such experiments, large wave-packet separation is impeded by the need for long interaction times and large momentum beam splitters, which cause susceptibility to dephasing and decoherence. Here we use light-pulse atom interferometry to realize quantum interference with wave packets separated by up to 54 centimetres on a timescale of 1 second. These results push quantum superposition into a new macroscopic regime, demonstrating that quantum superposition remains possible at the distances and timescales of everyday life. The sub-nanokelvin temperatures of the atoms and a compensation of transverse optical forces enable a large separation while maintaining an interference contrast of 28 per cent. In addition to testing the superposition principle in a new regime, large quantum superposition states are vital to exploring gravity with atom interferometers in greater detail. We anticipate that these states could be used to increase sensitivity in tests of the equivalence principle, measure the gravitational Aharonov-Bohm effect, and eventually detect gravitational waves and phase shifts associated with general relativity. PMID:26701053
Quantum superposition at the half-metre scale
NASA Astrophysics Data System (ADS)
Kovachy, T.; Asenbaum, P.; Overstreet, C.; Donnelly, C. A.; Dickerson, S. M.; Sugarbaker, A.; Hogan, J. M.; Kasevich, M. A.
2015-12-01
The quantum superposition principle allows massive particles to be delocalized over distant positions. Though quantum mechanics has proved adept at describing the microscopic world, quantum superposition runs counter to intuitive conceptions of reality and locality when extended to the macroscopic scale, as exemplified by the thought experiment of Schrödinger’s cat. Matter-wave interferometers, which split and recombine wave packets in order to observe interference, provide a way to probe the superposition principle on macroscopic scales and explore the transition to classical physics. In such experiments, large wave-packet separation is impeded by the need for long interaction times and large momentum beam splitters, which cause susceptibility to dephasing and decoherence. Here we use light-pulse atom interferometry to realize quantum interference with wave packets separated by up to 54 centimetres on a timescale of 1 second. These results push quantum superposition into a new macroscopic regime, demonstrating that quantum superposition remains possible at the distances and timescales of everyday life. The sub-nanokelvin temperatures of the atoms and a compensation of transverse optical forces enable a large separation while maintaining an interference contrast of 28 per cent. In addition to testing the superposition principle in a new regime, large quantum superposition states are vital to exploring gravity with atom interferometers in greater detail. We anticipate that these states could be used to increase sensitivity in tests of the equivalence principle, measure the gravitational Aharonov-Bohm effect, and eventually detect gravitational waves and phase shifts associated with general relativity.
[Superposition impact character of air pollution from decentralization docks in a freshwater port].
Liu, Jian-chang; Li, Xing-hua; Xu, Hong-lei; Cheng, Jin-xiang; Wang, Zhong-dai; Xiao, Yang
2013-05-01
Air pollution from freshwater port is mainly caused by dust pollution, including material loading and unloading dust, road dust, and wind erosion dust from stockpile, bare soil. The dust pollution from a single dock characterized in obvious difference with air pollution from multiple scattered docks. Jining Port of Shandong Province was selected as a case study to get superposition impact contribution of air pollution for regional air environment from multiple scattered docks and to provide technical support for system evaluation of port air pollution. The results indicate that (1) the air pollution from freshwater port occupies a low proportion of pollution impact on regional environmental quality because the port is consisted of serveral small scattered docks; (2) however, the geometric center of the region distributed by docks is severely affected with the most superposition of the air pollution; and (3) the ADMS model is helpful to attain an effective and integrated assessment to predict a superposition impact of multiple non-point pollution sources when the differences of high-altitude weather conditions was not considered on a large scale. PMID:23914566
Observing a coherent superposition of an atom and a molecule
Dowling, Mark R.; Bartlett, Stephen D.; Rudolph, Terry; Spekkens, Robert W.
2006-11-15
We demonstrate that it is possible, in principle, to perform a Ramsey-type interference experiment to exhibit a coherent superposition of a single atom and a diatomic molecule. This gedanken experiment, based on the techniques of Aharonov and Susskind [Phys. Rev. 155, 1428 (1967)], explicitly violates the commonly accepted superselection rule that forbids coherent superpositions of eigenstates of differing atom number. A Bose-Einstein condensate plays the role of a reference frame that allows for coherent operations analogous to Ramsey pulses. We also investigate an analogous gedanken experiment to exhibit a coherent superposition of a single boson and a fermion, violating the commonly accepted superselection rule forbidding coherent superpositions of states of differing particle statistics. In this case, the reference frame is realized by a multimode state of many fermions. This latter case reproduces all of the relevant features of Ramsey interferometry, including Ramsey fringes over many repetitions of the experiment. However, the apparent inability of this proposed experiment to produce well-defined relative phases between two distinct systems each described by a coherent superposition of a boson and a fermion demonstrates that there are additional, outstanding requirements to fully 'lift' the univalence superselection rule.
Azimuthally forced flames in an annular combustor
NASA Astrophysics Data System (ADS)
Worth, Nicholas; Dawson, James; Mastorakos, Epaminondas
2015-11-01
Thermoacoustic instabilities are more likely to occur in lean burn combustion systems, making their adoption both difficult and costly. At present, our knowledge of such phenomena is insufficient to produce an inherently stable combustor by design, and therefore an improved understanding of these instabilities has become the focus of a significant research effort. Recent experimental and numerical studies have demonstrated that the symmetry of annular chambers permit a range of self-excited azimuthal modes to be generated in annular geometry, which can make the study of isolated modes difficult. While acoustic forcing is common in single flame experiments, no equivalent for forced azimuthal modes in an annular chamber have been demonstrated. The present investigation focuses on the novel application of acoustic forcing to a laboratory scale annular combustor, in order to generate azimuthal standing wave modes at a prescribed frequency and amplitude. The results focus on the ability of the method to isolate the mode of oscillation using experimental pressure and high speed OH* measurements. The successful excitation of azimuthal modes demonstrated represents an important step towards improving our fundamental understanding of this phenomena in practically relevant geometry.
Ultrasonic field modeling for immersed components using Gaussian beam superposition.
Spies, Martin
2007-05-01
The Gaussian beam (GB) superposition approach can be applied to model ultrasound propagation in complex-structured materials and components. In this article, progress made in extending and applying the Gaussian beam superposition technique to model the beam fields generated by transducers with flat and focused rectangular apertures as well as with circular focused apertures is addressed. The refraction of transducer beam fields through curved surfaces is illustrated by calculation results for beam fields generated in curved components during immersion testing. In particular, the following developments are put forward: (i) the use of individually determined sets of GBs to model transducer beam fields with a number of less than ten beams; (ii) the application of the GB representation of rectangular transducers to focusing probes, as well as to the problem of transmission through interfaces; and (iii) computationally efficient transient modeling by superposition of 'temporally limited' GBs. PMID:17335863
Non-coaxial superposition of vector vortex beams.
Aadhi, A; Vaity, Pravin; Chithrabhanu, P; Reddy, Salla Gangi; Prabakar, Shashi; Singh, R P
2016-02-10
Vector vortex beams are classified into four types depending upon spatial variation in their polarization vector. We have generated all four of these types of vector vortex beams by using a modified polarization Sagnac interferometer with a vortex lens. Further, we have studied the non-coaxial superposition of two vector vortex beams. It is observed that the superposition of two vector vortex beams with same polarization singularity leads to a beam with another kind of polarization singularity in their interaction region. The results may be of importance in ultrahigh security of the polarization-encrypted data that utilizes vector vortex beams and multiple optical trapping with non-coaxial superposition of vector vortex beams. We verified our experimental results with theory. PMID:26906384
Dissipative Optomechanical Preparation of Macroscopic Quantum Superposition States.
Abdi, M; Degenfeld-Schonburg, P; Sameti, M; Navarrete-Benlloch, C; Hartmann, M J
2016-06-10
The transition from quantum to classical physics remains an intensely debated question even though it has been investigated for more than a century. Further clarifications could be obtained by preparing macroscopic objects in spatial quantum superpositions and proposals for generating such states for nanomechanical devices either in a transient or a probabilistic fashion have been put forward. Here, we introduce a method to deterministically obtain spatial superpositions of arbitrary lifetime via dissipative state preparation. In our approach, we engineer a double-well potential for the motion of the mechanical element and drive it towards the ground state, which shows the desired spatial superposition, via optomechanical sideband cooling. We propose a specific implementation based on a superconducting circuit coupled to the mechanical motion of a lithium-decorated monolayer graphene sheet, introduce a method to verify the mechanical state by coupling it to a superconducting qubit, and discuss its prospects for testing collapse models for the quantum to classical transition. PMID:27341233
Dissipative Optomechanical Preparation of Macroscopic Quantum Superposition States
NASA Astrophysics Data System (ADS)
Abdi, M.; Degenfeld-Schonburg, P.; Sameti, M.; Navarrete-Benlloch, C.; Hartmann, M. J.
2016-06-01
The transition from quantum to classical physics remains an intensely debated question even though it has been investigated for more than a century. Further clarifications could be obtained by preparing macroscopic objects in spatial quantum superpositions and proposals for generating such states for nanomechanical devices either in a transient or a probabilistic fashion have been put forward. Here, we introduce a method to deterministically obtain spatial superpositions of arbitrary lifetime via dissipative state preparation. In our approach, we engineer a double-well potential for the motion of the mechanical element and drive it towards the ground state, which shows the desired spatial superposition, via optomechanical sideband cooling. We propose a specific implementation based on a superconducting circuit coupled to the mechanical motion of a lithium-decorated monolayer graphene sheet, introduce a method to verify the mechanical state by coupling it to a superconducting qubit, and discuss its prospects for testing collapse models for the quantum to classical transition.
Seeing lens imaging as a superposition of multiple views
NASA Astrophysics Data System (ADS)
Grusche, Sascha
2016-01-01
In the conventional approach to lens imaging, rays are used to map object points to image points. However, many students want to think of the image as a whole. To answer this need, Kepler’s ray drawing is reinterpreted in terms of shifted camera obscura images. These images are uncovered by covering the lens with pinholes. Thus, lens imaging is seen as a superposition of sharp images from different viewpoints, so-called elemental images. This superposition is simulated with projectors, and with transparencies. Lens ray diagrams are constructed based on elemental images; the conventional construction method is included as a special case.
Tight bounds on the concurrence of quantum superpositions
Niset, J.; Cerf, N. J.
2007-10-15
The entanglement content of superpositions of quantum states is investigated based on a measure called concurrence. Given a bipartite pure state in arbitrary dimension written as the quantum superposition of two other such states, we find simple inequalities relating the concurrence of the state to that of its components. We derive an exact expression for the concurrence when the component states are biorthogonal and provide elegant upper and lower bounds in all other cases. For quantum bits, our upper bound is tighter than the previously derived bound [N. Linden et al., Phys. Rev. Lett. 97, 100502 (2006)].
Orbital angular momentum of superposition of identical shifted vortex beams.
Kovalev, A A; Kotlyar, V V
2015-10-01
We have formulated and proven the following theorem: the superposition of an arbitrary number of arbitrarily off-axis, identical nonparaxial optical vortex beams of arbitrary radially symmetric shape, integer topological charge n, and arbitrary real weight coefficients has the normalized orbital angular momentum (OAM) equal to that of individual constituent identical beams. This theorem enables generating vortex laser beams with different (not necessarily radially symmetric) intensity profiles but identical OAM. Superpositions of Bessel, Hankel-Bessel, Bessel-Gaussian, and Laguerre-Gaussian beams with the same OAM are discussed. PMID:26479934
Management of Periocular Granuloma Annulare Using Topical Dapsone
Patel, Mayha; Shitabata, Paul; Horowitz, David
2015-01-01
Granuloma annulare is a disease characterized by granulomatous inflammation of the dermis. Localized granuloma annulare may resolve spontaneously, while generalized granuloma annulare may persist for decades. The authors present the case of a 41-year-old Hispanic man with a two-week history of periocular granuloma annulare. Due to previously reported success in the use of systemic dapsone for the treatment of granuloma annulare, and the periocular proximity of the patient’s lesion, topical dapsone was used for treatment. Various additional therapies for the management of granuloma annulare have been reported, such as topical and systemic steroids, isotretinoin, pentoxifylline, cyclosporine, Interferon gamma, potassium iodide, nicotinamide, niacinamide, salicylic acid, fumaric acid ester, etanercept, infliximab, and hydroxychloroquine. Additional clinical trials are necessary to further evaluate the effectiveness of topical dapsone in the management of granuloma annulare. PMID:26203321
LDV measurements in an annular combustor model
NASA Astrophysics Data System (ADS)
Barron, Dean A.
1986-08-01
The design and setup of a Laser Doppler Velocimeter (LDV) system used to take velocity measurements in an annular combustor model are covered. The annular combustor model is of contemporary design using 60 degree flat vane swirlers, producing a strong recirculation zone. Detailed measurements are taken of the swirler inlet air flow and of the downstream enclosed swirling flow. The laser system used is a two color, two component system set up in forward scatter. Detailed are some of the special considerations needed for LDV use in the confined turbulent flow of the combustor model. The LDV measurements in a single swirler rig indicated that the flow changes radically in the first duct height. After this, a flow profile is set up and remains constant in shape. The magnitude of the velocities gradually decays due to viscous damping.
Development of an Advanced Annular Combustor
NASA Technical Reports Server (NTRS)
Rusnak, J. P.; Shadowen, J. H.
1969-01-01
The objective of the effort described in this report was to determine the structural durability of a full-scale advanced annular turbojet combustor using ASTM A-1 type fuel and operating at conditions typical of advanced supersonic aircraft. A full-scale annular combustor of the ram-induction type was fabricated and subjected to a 325-hour cyclic endurance test at conditions representative of operation in a Mach 3.0 aircraft. The combustor exhibited extensive cracking and scoop burning at the end of the test program. But these defects had no appreciable effect on combustor performance, as performance remained at a high level throughout the endurance program. Most performance goals were achieved with pressure loss values near 6% and 8%, and temperature rise variation ratio (deltaTVR) values near 1.25 and l.22 at takeoff and cruise conditions, respectively. Combustion efficiencies approached l004 and the exit radial temperature profiles were approximately as desired.
LDV Measurements in an Annular Combustor Model
NASA Technical Reports Server (NTRS)
Barron, Dean A.
1996-01-01
This thesis covers the design and setup of a laser doppler velocimeter (LDV) system used to take velocity measurements in an annular combustor model. The annular combustor model is of contemporary design using 60 degree flat vane swirlers, producing a strong recirculation zone. Detailed measurements are taken of the swirler inlet air flow and of the downstream enclosed swirling flow. The laser system used is a two color, two component system set up in forward scatter. Detailed are some of the special considerations needed for LDV use in the confined turbulent flow of the combustor model. LDV measurements in a single swirler rig indicated that the flow changes radically in the first duct height. After this, a flow profile is set up and remains constant in shape. The magnitude of the velocities gradually decays due to viscous damping.
Annular flow film characteristics in variable gravity.
MacGillivray, Ryan M; Gabriel, Kamiel S
2002-10-01
Annular flow is a frequently occurring flow regime in many industrial applications. The need for a better understanding of this flow regime is driven by the desire to improve the design of many terrestrial and space systems. Annular two-phase flow occurs in the mining and transportation of oil and natural gas, petrochemical processes, and boilers and condensers in heating and refrigeration systems. The flow regime is also anticipated during the refueling of space vehicles, and thermal management systems for space use. Annular flow is mainly inertia driven with little effect of buoyancy. However, the study of this flow regime is still desirable in a microgravity environment. The influence of gravity can create an unstable, chaotic film. The absence of gravity, therefore, allows for a more stable and axisymmetric film. Such conditions allow for the film characteristics to be easily studied at low gas flow rates. Previous studies conducted by the Microgravity Research Group dealt with varying the gas or liquid mass fluxes at a reduced gravitational acceleration.(1,2) The study described here continues this work by examining the effect of changing the gravitational acceleration (hypergravity) on the film characteristics. In particular, the film thickness and the associated pressure drops are examined. The film thickness was measured using a pair of two-wire conductance probes. Experimental data was collected over a range of annular flow set points by changing the liquid and gas mass flow rates, the liquid-to-gas density ratio and the gravitational acceleration. The liquid-to-gas density ratio was varied by collecting data with helium-water and air-water at the same flow rates. The gravitational effect was examined by collecting data during the microgravity and pull-up (hypergravity) portions of the parabolic flights. PMID:12446332
Neoclassical transport in an annular penning trap
Robertson, S.
1997-07-01
A modified Penning trap is described with an annular confinement region and a toroidal magnetic field. A non-neutral electron plasma is confined axially by an electrostatic field and, in the radial direction, particles are constrained to lie within a small drift distance of a cylindrical flux surface. Drift orbits of all particles are banana-shaped and collisions cause neoclassical transport. {copyright} {ital 1997 American Institute of Physics.}
Endoscopic measurements using a panoramic annular lens
NASA Technical Reports Server (NTRS)
Gilbert, John A.; Matthys, Donald R.
1992-01-01
The objective of this project was to design, build, demonstrate, and deliver a prototype system for making measurements within cavities. The system was to utilize structured lighting as the means for making measurements and was to rely on a stationary probe, equipped with a unique panoramic annular lens, to capture a cylindrical view of the illuminated cavity. Panoramic images, acquired with a digitizing camera and stored in a desk top computer, were to be linearized and analyzed by mouse-driven interactive software.
Annular and Total Solar Eclipses of 2003
NASA Technical Reports Server (NTRS)
Espenak, Fred; Anderson, Jay
2002-01-01
On Saturday, 2003 May 31, an annular eclipse of the Sun will be visible from a broad corridor that traverses the North Atlantic. The path of the Moon's antumbral shadow begins in northern Scotland, crosses Iceland and central Greenland, and ends at sunrise in Baffin Bay (Canada). A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes most of Europe, the Middle East, central and northern Asia, and northwestern North America. The trajectory of the Moon's shadow is quite unusual during this event. The shadow axis passes to the far north where it barely grazes Earth's surface. In fact, the northern edge of the antumbra actually misses Earth so that one path limit is defined by the day/night terminator rather than by the shadow's upper edge. As a result, the track of annularity has a peculiar "D" shape that is nearly 1200 kilometers wide. Since the eclipse occurs just three weeks prior to the northern summer solstice, Earth's northern axis is pointed sunwards by 22.8 deg. As seen from the Sun, the antumbral shadow actually passes between the North Pole and the terminator. As a consequence of this extraordinary geometry, the path of annularity runs from east to west rather than the more typical west to east. The event transpires near the Moon's ascending node in Taurus five degrees north of Aldebaran. Since apogee occurs three days earlier (May 28 at 13 UT), the Moon's apparent diameter (29.6 arc-minutes) is still too small to completely cover the Sun (31.6 arc-minutes) resulting in an annular eclipse.
Atypical scabies presenting as annular patches.
Hossain, Delwar
2014-01-01
Scabies is a common parasitic disease that can be recognized by the development of itchy lesions and a predilection for certain places on the body. It may infrequently present with patchy lesions. We report a patient with well-defined annular patches. Histopathology showed an egg of the scabies mite in the epidermis. Treatment with permethrin cream resulted in complete resolution of her disease. PMID:22967356
The Annular Suspension and Pointing System /ASPS/
NASA Technical Reports Server (NTRS)
Anderson, W. W.; Woolley, C. T.
1978-01-01
The Annular Suspension and Pointing System (ASPS) may be attached to a carrier vehicle for orientation, mechanical isolation, and fine pointing purposes applicable to space experiments. It has subassemblies for both coarse and vernier pointing. A fourteen-degree-of-freedom simulation of the ASPS mounted on a Space Shuttle has yielded initial performance data. The simulation describes: the magnetic actuators, payload sensors, coarse gimbal assemblies, control algorithms, rigid body dynamic models of the payload and Shuttle, and a control system firing model.
Annular Alopecia Areata: Report of Two Cases
Bansal, Manish; Manchanda, Kajal; Pandey, SS
2013-01-01
Alopecia areata (AA) is an auto-immune disorder characterized by the appearance of non-scarring bald patches affecting the hair bearing areas of the body. Scalp is the most common site of involvement. AA can affect any age group. The usual pattern of the hair loss is oval or round. We hereby, report two cases of annular and circinate pattern of AA due to its unusual morphology. PMID:24403774
Performance of annular high frequency thermoacoustic engines
NASA Astrophysics Data System (ADS)
Rodriguez, Ivan A.
This thesis presents studies of the behavior of miniature annular thermoacoustic prime movers and the imaging of the complex sound fields using PIV inside the small acoustic wave guides when driven by a temperature gradient. Thermoacoustic engines operating in the standing wave mode are limited in their acoustic efficiency by a high degree of irreversibility that is inherent in how they work. Better performance can be achieved by using traveling waves in the thermoacoustic devices. This has led to the development of an annular high frequency thermoacoustic prime mover consisting of a regenerator, which is a random stack in-between a hot and cold heat exchanger, inside an annular waveguide. Miniature devices were developed and studied with operating frequencies in the range of 2-4 kHz. This corresponds to an average ring circumference of 11 cm for the 3 kHz device, the resonator bore being 6 mm. A similar device of 11 mm bore, length of 18 cm was also investigated; its resonant frequency was 2 kHz. Sound intensities as high as 166.8 dB were generated with limited heat input. Sound power was extracted from the annular structure by an impedance-matching side arm. The nature of the acoustic wave generated by heat was investigated using a high speed PIV instrument. Although the acoustic device appears symmetric, its performance is characterized by a broken symmetry and by perturbations that exist in its structure. Effects of these are observed in the PIV imaging; images show axial and radial components. Moreover, PIV studies show effects of streaming and instabilities which affect the devices' acoustic efficiency. The acoustic efficiency is high, being of 40% of Carnot. This type of device shows much promise as a high efficiency energy converter; it can be reduced in size for microcircuit applications.
Annular feed air breathing fuel cell stack
Wilson, Mahlon S.; Neutzler, Jay K.
1997-01-01
A stack of polymer electrolyte fuel cells is formed from a plurality of unit cells where each unit cell includes fuel cell components defining a periphery and distributed along a common axis, where the fuel cell components include a polymer electrolyte membrane, an anode and a cathode contacting opposite sides of the membrane, and fuel and oxygen flow fields contacting the anode and the cathode, respectively, wherein the components define an annular region therethrough along the axis. A fuel distribution manifold within the annular region is connected to deliver fuel to the fuel flow field in each of the unit cells. The fuel distribution manifold is formed from a hydrophilic-like material to redistribute water produced by fuel and oxygen reacting at the cathode. In a particular embodiment, a single bolt through the annular region clamps the unit cells together. In another embodiment, separator plates between individual unit cells have an extended radial dimension to function as cooling fins for maintaining the operating temperature of the fuel cell stack.
Vibration analysis of annular-like plates
NASA Astrophysics Data System (ADS)
Cheng, L.; Li, Y. Y.; Yam, L. H.
2003-05-01
The existence of eccentricity of the central hole for an annular plate results in a significant change in the natural frequencies and mode shapes of the structure. In this paper, the vibration analysis of annular-like plates is presented based on numerical and experimental approaches. Using the finite element analysis code Nastran, the effects of the eccentricity, hole size and boundary condition on vibration modes are investigated systematically through both global and local analyses. The results show that analyses for perfect symmetric conditions can still roughly predict the mode shapes of "recessive" modes of the plate with a slightly eccentric hole. They will, however, lead to erroneous results for "dominant" modes. In addition, the residual displacement mode shape is verified as an effective parameter for identifying damage occurring in plate-like structures. Experimental modal analysis on a clamped-free annular-like plate is performed, and the results obtained reveal good agreement with those obtained by numerical analysis. This study provides guidance on modal analysis, vibration measurement and damage detection of plate-like structures.
Multidimensional detonation propagation modeled via nonlinear shock wave superposition
NASA Astrophysics Data System (ADS)
Higgins, Andrew; Mehrjoo, Navid
2010-11-01
Detonation waves in gases are inherently multidimensional due to their cellular structure, and detonations in liquids and heterogeneous solids are often associated with instabilities and stochastic, localized reaction centers (i.e., hot spots). To explore the statistical nature of detonation dynamics in such systems, a simple model that idealizes detonation propagation as an ensemble of interacting blast waves originating from spatially random point sources has been proposed. Prior results using this model exhibited features that have been observed in real detonating systems, such as anomalous scaling between axisymmetric and two-dimensional geometries. However, those efforts used simple linear superposition of the blast waves. The present work uses a model of blast wave superposition developed for multiple-source explosions (the LAMB approximation) that incorporates the nonlinear interaction of shock waves analytically, permitting the effect of a more physical model of blast wave interaction to be explored. The results are suggestive of a universal behavior in systems of spatially randomized energy sources.
Nonclassicality tests and entanglement witnesses for macroscopic mechanical superposition states
NASA Astrophysics Data System (ADS)
Gittsovich, Oleg; Moroder, Tobias; Asadian, Ali; Gühne, Otfried; Rabl, Peter
2015-02-01
We describe a set of measurement protocols for performing nonclassicality tests and the verification of entangled superposition states of macroscopic continuous variable systems, such as nanomechanical resonators. Following earlier works, we first consider a setup where a two-level system is used to indirectly probe the motion of the mechanical system via Ramsey measurements and discuss the application of this method for detecting nonclassical mechanical states. We then show that the generalization of this technique to multiple resonator modes allows the conditioned preparation and the detection of entangled mechanical superposition states. The proposed measurement protocols can be implemented in various qubit-resonator systems that are currently under experimental investigation and find applications in future tests of quantum mechanics at a macroscopic scale.
Quantum Delayed-Choice Experiment and Wave-Particle Superposition
NASA Astrophysics Data System (ADS)
Guo, Qi; Cheng, Liu-Yong; Wang, Hong-Fu; Zhang, Shou
2015-08-01
We propose a simple implementation scheme of quantum delayed-choice experiment in linear optical system without initial entanglement resource. By choosing different detecting devices, one can selectively observe the photon's different behaviors after the photon has been passed the Mach-Zehnder interferometer. The scheme shows that the photon's wave behavior and particle behavior can be observed with a single experimental setup by postselection, that is, the photon can show the superposition behavior of wave and particle. Especially, we compare the wave-particle superposition behavior and the wave-particle mixture behavior in detail, and find the quantum interference effect between wave and particle behavior, which may be helpful to reveal the nature of photonessentially.
Functional specifications of the annular suspension pointing system, appendix A
NASA Technical Reports Server (NTRS)
Edwards, B.
1980-01-01
The Annular Suspension Pointing System is described. The Design Realization, Evaluation and Modelling (DREAM) system, and its design description technique, the DREAM Design Notation (DDN) is employed.
Tailoring quantum superpositions with linearly polarized amplitude-modulated light
Pustelny, S.; Koczwara, M.; Cincio, L.; Gawlik, W.
2011-04-15
Amplitude-modulated nonlinear magneto-optical rotation is a powerful technique that offers a possibility of controllable generation of given quantum states. In this paper, we demonstrate creation and detection of specific ground-state magnetic-sublevel superpositions in {sup 87}Rb. By appropriate tuning of the modulation frequency and magnetic-field induction the efficiency of a given coherence generation is controlled. The processes are analyzed versus different experimental parameters.
Quantum Superposition, Collapse, and the Default Specification Principle
NASA Astrophysics Data System (ADS)
Nikkhah Shirazi, Armin
2014-03-01
Quantum Superposition and collapse lie at the heart of the difficulty in understanding what quantum mechanics is exactly telling us about reality. We present here a principle which permits one to formulate a simple and general mathematical model that abstracts these features out of quantum theory. A precise formulation of this principle in terms of a set-theoretic axiom added to standard set theory may directly connect the foundations of physics to the foundations of mathematics.
Macroscopic superposition of ultracold atoms with orbital degrees of freedom
Garcia-March, M. A.; Carr, L. D.; Dounas-Frazer, D. R.
2011-04-15
We introduce higher dimensions into the problem of Bose-Einstein condensates in a double-well potential, taking into account orbital angular momentum. We completely characterize the eigenstates of this system, delineating new regimes via both analytical high-order perturbation theory and numerical exact diagonalization. Among these regimes are mixed Josephson- and Fock-like behavior, crossings in both excited and ground states, and shadows of macroscopic superposition states.
Sensing Super-position: Visual Instrument Sensor Replacement
NASA Technical Reports Server (NTRS)
Maluf, David A.; Schipper, John F.
2006-01-01
The coming decade of fast, cheap and miniaturized electronics and sensory devices opens new pathways for the development of sophisticated equipment to overcome limitations of the human senses. This project addresses the technical feasibility of augmenting human vision through Sensing Super-position using a Visual Instrument Sensory Organ Replacement (VISOR). The current implementation of the VISOR device translates visual and other passive or active sensory instruments into sounds, which become relevant when the visual resolution is insufficient for very difficult and particular sensing tasks. A successful Sensing Super-position meets many human and pilot vehicle system requirements. The system can be further developed into cheap, portable, and low power taking into account the limited capabilities of the human user as well as the typical characteristics of his dynamic environment. The system operates in real time, giving the desired information for the particular augmented sensing tasks. The Sensing Super-position device increases the image resolution perception and is obtained via an auditory representation as well as the visual representation. Auditory mapping is performed to distribute an image in time. The three-dimensional spatial brightness and multi-spectral maps of a sensed image are processed using real-time image processing techniques (e.g. histogram normalization) and transformed into a two-dimensional map of an audio signal as a function of frequency and time. This paper details the approach of developing Sensing Super-position systems as a way to augment the human vision system by exploiting the capabilities of the human hearing system as an additional neural input. The human hearing system is capable of learning to process and interpret extremely complicated and rapidly changing auditory patterns. The known capabilities of the human hearing system to learn and understand complicated auditory patterns provided the basic motivation for developing an
Interplay of gravitation and linear superposition of different mass eigenstates
NASA Astrophysics Data System (ADS)
Ahluwalia, D. V.; Burgard, C.
1998-04-01
The interplay of gravitation and the quantum-mechanical principle of linear superposition induces a new set of neutrino oscillation phases. These ensure that the flavor-oscillation clocks, inherent in the phenomenon of neutrino oscillations, redshift precisely as required by Einstein's theory of gravitation. The physical observability of these phases in the context of the solar neutrino anomaly, type-II supernova, and certain atomic systems is briefly discussed.
Single-Atom Gating of Quantum State Superpositions
Moon, Christopher
2010-04-28
The ultimate miniaturization of electronic devices will likely require local and coherent control of single electronic wavefunctions. Wavefunctions exist within both physical real space and an abstract state space with a simple geometric interpretation: this state space - or Hilbert space - is spanned by mutually orthogonal state vectors corresponding to the quantized degrees of freedom of the real-space system. Measurement of superpositions is akin to accessing the direction of a vector in Hilbert space, determining an angle of rotation equivalent to quantum phase. Here we show that an individual atom inside a designed quantum corral1 can control this angle, producing arbitrary coherent superpositions of spatial quantum states. Using scanning tunnelling microscopy and nanostructures assembled atom-by-atom we demonstrate how single spins and quantum mirages can be harnessed to image the superposition of two electronic states. We also present a straightforward method to determine the atom path enacting phase rotations between any desired state vectors. A single atom thus becomes a real-space handle for an abstract Hilbert space, providing a simple technique for coherent quantum state manipulation at the spatial limit of condensed matter.
Thread-annular flow in vertical pipes
NASA Astrophysics Data System (ADS)
Frei, Ch.; Lüscher, P.; Wintermantel, E.
2000-05-01
Thread injection is a promising method for different minimally invasive medical applications. This paper documents an experimental study dealing with an axially moving thread in annular pipe flow. Mass flow and axial force on the thread are measured for a 0.46 mm diameter thread in pipes with diameters between 0.55 and 1.35 mm. The experiments with thread velocities of up to 1.5 ms[minus sign]1 confirm the findings of theoretical studies that for clinical requirements the radius ratio between thread and pipe is crucial for the adjustments of mass ow and force on the thread.
Pseudomonas aeruginosa infection mimicking erythema annulare centrifugum.
Czechowicz, R T; Warren, L J; Moore, L; Saxon, B
2001-02-01
A 3-year-old girl receiving chemotherapy for acute lymphocytic leukaemia developed a rapidly expanding red annular plaque on her thigh, initially without signs of systemic toxicity or local pain. Subsequently she developed Pseudomonas aeruginosa sepsis and purpura at the leading edge of the plaque. Skin biopsy showed an extensive necrotizing vasculitis with numerous Gram-negative bacilli in the blood vessel walls. In immunocompromised individuals, skin biopsy and culture of cutaneous lesions for bacteria and fungi should be considered even in the absence of signs of systemic toxicity or multiple lesions. PMID:11233725
Endoscopic inspection using a panoramic annular lens
NASA Technical Reports Server (NTRS)
Gilbert, John A.; Matthys, Donald R.
1991-01-01
The objective of this one year study was to design, build, and demonstrate a prototype system for cavity inspection. A cylindrical view of the cavity interior was captured in real time through a compound lens system consisting of a unique panoramic annular lens and a collector lens. Images, acquired with a digitizing camera and stored in a desktop computer, were manipulated using image processing software to aid in visual inspection and qualitative analysis. A detailed description of the lens and its applications is given.
Interfacial friction in cocurrent upward annular flow
NASA Astrophysics Data System (ADS)
Hossfeld, L. M.; Bharathan, D.; Wallis, G. B.; Richter, H. J.
1982-03-01
Cocurrent upward annular flow is investigated, with an emphasis on correlating and predicting pressure drop. Attention is given to the characteristics of the liquid flow in the film, and the interaction of the core with the film. Alternate approaches are discussed for correlating suitably defined interfacial friction factors. Both approaches are dependent on knowledge of the entrainment in order to make predictions. Dimensional analysis is used to define characteristic parameters of the flow and an effort is made to determine, to the extent possible, the influences of these parameters on the interfacial friction factor.
Experiment of rocket-ram annular combustor
NASA Astrophysics Data System (ADS)
Yatsuyanagi, N.; Sakamoto, H.; Sato, K.; Ono, F.; Sasaki, M.; Takahashi, M.
In this experiment, the double-nozzle type of rocket-ram annular combustor with a total thrust of 5kN was designed and tested with varying ratios of thrust produced by rocket and ram. Thrust and pressure distribution along the common expansion nozzle, i.e., the ram combustor nozzle, were measured to investigate the effect of interaction of the two expansion gases on thrust. Enhancement of specific impulse was verified by the experiments. That is, the specific impulse gains in rocket-ram parallel operation, the ratio of rocket thrust to ram thrust being 50 to 50, were found to be 190 percent of gains in pure rocket operation.
Duration test of an annular colloid thruster.
NASA Technical Reports Server (NTRS)
Perel, J.; Mahoney, J. F.; Daley, H. L.
1972-01-01
An annular colloid thruster was continuously operated for 1023 hours. Performance was stable with no sparking and negligible drain currents observed. An average thrust of 25.1 micropounds and an average specific impulse of 1160 seconds were obtained at an accelerating voltage of 15 k he thruster exhaust beam was continuously neutralized using electrons and electrostatic vectoring was demonstrated periodically. The only clear trend with time was an increase in specific impulse during the last third of the test period. From these results the thruster lifetime was estimated to be over an order of magnitude greater than the test duration.
Wave turbulence in annular wave tank
NASA Astrophysics Data System (ADS)
Onorato, Miguel; Stramignoni, Ettore
2014-05-01
We perform experiments in an annular wind wave tank at the Dipartimento di Fisica, Universita' di Torino. The external diameter of the tank is 5 meters while the internal one is 1 meter. The tank is equipped by two air fans which can lead to a wind of maximum 5 m/s. The present set up is capable of studying the generation of waves and the development of wind wave spectra for large duration. We have performed different tests including different wind speeds. For large wind speed we observe the formation of spectra consistent with Kolmogorv-Zakharov predictions.
Tank evaluation system shielded annular tank application
Freier, D.A.
1988-10-04
TEST (Tank Evaluation SysTem) is a research project utilizing neutron interrogation techniques to analyze the content of nuclear poisons and moderators in tank shielding. TEST experiments were performed on an experimental SAT (Shielded Annular Tank) at the Rocky Flats Plant. The purpose of these experiments was threefold: (1) to assess TEST application to SATs, (2) to determine if Nuclear Safety inspection criteria could be met, and (3) to perform a preliminary calibration of TEST for SATs. Several experiments were performed, including measurements of 11 tank shielding configurations, source-simulated holdup experiments, analysis of three detector modes, resolution studies, and TEST scanner geometry experiments. 1 ref., 21 figs., 4 tabs.
Nonlinear features of Northern Annular Mode variability
NASA Astrophysics Data System (ADS)
Fu, Zuntao; Shi, Liu; Xie, Fenghua; Piao, Lin
2016-05-01
Nonlinear features of daily Northern Annular Mode (NAM) variability at 17 pressure levels are quantified by two different measures. One is nonlinear correlation, and the other is time-irreversible symmetry. Both measures show that there are no significant nonlinear features in NAM variability at the higher pressure levels, however as the pressure level decreases, the strength of nonlinear features in NAM variability becomes predominant. This indicates that in order to reach better prediction of NAM variability in the lower pressure levels, nonlinear features must be taken into consideration to build suitable models.
Optical manipulation using optimal annular vortices.
Paez-Lopez, Rafael; Ruiz, Ulises; Arrizon, Victor; Ramos-Garcia, Ruben
2016-09-01
We discuss a simple method to generate a configurable annular vortex beam (AVB) with the maximum possible peak intensity, employing a phase hologram whose transmittance is the phase of a Bessel beam. Due to its maximum intensity, the AVB provides the optimal density of the orbital angular moment. Another attribute of the generated AVB is the relatively high invariance of the intensity profile when the topological charge is changed. We demonstrate the advantages and flexibility of these AVBs for optical trapping applications. PMID:27607992
Uncertainty methodology for the strongly coupled physical phenomena associated with annular flow
Lane, J. W.; Aumiller Jr, D. L.
2012-07-01
Best-Estimate plus Uncertainty (BEPU) methods are slowly supplanting the use of deterministic analysis methods for thermal-hydraulic analyses. As the uncertainty methodologies evolve it is expected that, where both experimental techniques allow and data are available, there will be a shift to quantifying the uncertainty in increasingly more fundamental parameters. For example, for annular flow in a three-field analysis environment (vapor, liquid film, droplet), the driving parameters would be: a) film interfacial shear stress, b) droplet drag, c) droplet entrainment rate and d) droplet deposition rate. An improved annular flow modeling package was recently developed and implemented in an in-house version of the COBRA-TF best-estimate subchannel analysis tool (Lane, 2009). Significant improvement was observed in the code-to-data predictions of several steam-water annular flow tests following the implementation of this modeling package; however, to apply this model set in formal BEPU analysis requires uncertainty distributions to be determined. The unique aspect of annular flow, and the topic of the present work, is the strong coupling between the interfacial drag, entrainment and deposition phenomena. Ideally the uncertainty in each phenomenon would be isolated; however, the situation is further complicated by an inability to experimentally isolate and measure the individual rate processes (particularly entrainment rate), which results in available experimental data that are inherently integral in nature. This paper presents a methodology for isolating the individual physical phenomena of interest, to the extent that the currently available experimental data allow, and developing the corresponding uncertainty distributions for annular flow. (authors)
Laminar heat transfer in annular sector ducts
Soliman, H.M. )
1987-02-01
The continuing interest in compact heat exchangeers has created the need for friction factor and Nusselt number data for different passage shapes. It has long been recognized that circular tube results are generally not applicable to noncircular passages even when the hydraulic diameter is used as the characteristic dimension. Hence, design data should be generated for each passage individually, and a good source of such information is Shah and London. One duct geometry for which complete design information does not appear to be available in the open literature is that of annular sector ducts. Such configuration is encountered in multipassage internally finned tubes and many other compact het exchanger applications. The fluid flow problem for this configuration has been solved by Sparrow et al., and more recently by Niida. However, to the beest of the author's knowledge, the heat transfer results are not available yet. The purpose of this note is to summarize the analysis and results of fluid flow and heat transfer in annular sector ducts.
NWIS MEASUREMENTS FOR URANIUM METAL ANNULAR CASTINGS
MATTINGLY, J.K.; VALENTINE, T.E.; MIHALCZO, J.T.
1998-03-13
This report describes measurements performed with annular uranium metal castings of different enrichments to investigate the use of {sup 252}Cf-source-driven noise analysis measurements as a means to quantify the amount of special nuclear material (SNM) in the casting. This work in FY 97 was sponsored by the Oak Ridge Y-12 Plant and the DOE Office of Technology Development Programs. Previous measurements and calculational studies have shown that many of the signatures obtained from the source-driven measurement are very sensitive to fissile mass. Measurements were performed to assess the applicability of this method to standard annular uranium metal castings at the Oak Ridge Y-12 plant under verification by the International Atomic Energy Agency (IAEA) using the Nuclear Weapons Identification System (NWIS) processor. Before the measurements with different enrichments, a limited study of source-detector-casting moderator configurations was performed to enhance the correlated information. These configurations consisted of a casting with no reflector and with various thicknesses of polyethylene reflectors up to 10.16 cm in 2.54 cm steps. The polyethylene moderator thickness of 7.62 cm was used for measurements with castings of different enrichments reported here. The sensitivity of the measured parameters to fissile mass was investigated using four castings each with a different enrichment. The high sensitivity of this measurement method to fissile mass and to other material and configurations provides some advantages over existing safeguards methods.
Detonation diffraction from an annular channel
NASA Astrophysics Data System (ADS)
Meredith, James; Ng, Hoi Dick; Lee, John H. S.
2010-12-01
In this study, gaseous detonation diffraction from an annular channel was investigated with a streak camera and the critical pressure for transmission of the detonation wave was obtained. The annular channel was used to approximate an infinite slot resulting in cylindrically expanding detonation waves. Two mixtures, stoichiometric acetylene-oxygen and stoichiometric acetylene-oxygen with 70% Ar dilution, were tested in a 4.3 and 14.3 mm channel width ( W). The undiluted and diluted mixtures were found to have values of the critical channel width over the cell size around 3 and 12 respectively. Comparing these results to values of the critical diameter ( d c ), in which a spherical detonation occurs, a value of critical d c / W c near 2 is observed for the highly diluted mixture. This value corresponds to the geometrical factor of the curvature term between a spherical and cylindrical diverging wave. Hence, the result is in support of Lee's proposed mechanism [Lee in Dynamics of Exothermicity, pp. 321, Gordon and Breach, Amsterdam, 1996] for failure due to diffraction based on curvature in stable mixtures such as those highly argon diluted with very regular detonation cellular patterns.
Annular and Total Solar Eclipses of 2010
NASA Technical Reports Server (NTRS)
Espenak, Fred; Anderson, J.
2008-01-01
While most NASA eclipse bulletins cover a single eclipse, this publication presents predictions for two solar eclipses during 2010. This has required a different organization of the material into the following sections. Section 1 -- Eclipse Predictions: The section consists of a general discussion about the eclipse path maps, Besselian elements, shadow contacts, eclipse path tables, local circumstances tables, and the lunar limb profile. Section 2 -- Annular Solar Eclipse of 2010 Ja n 15: The section covers predictions and weather prospects for the annular eclipse. Section 3 -- Total Solar Eclipse of 2010 Jul 11: The se ction covers predictions and weather prospects for the total eclipse. Section 4 -- Observing Eclipses: The section provides information on eye safety, solar filters, eclipse photography, and making contact timings from the path limits. Section 5 -- Eclipse Resources: The final section contains a number of resources including information on the IAU Working Group on Eclipses, the Solar Eclipse Mailing List, the NASA eclipse bulletins on the Internet, Web sites for the two 2010 eclipses, and a summary identifying the algorithms, ephemerides, and paramete rs used in the eclipse predictions.
Controlling the pressure within an annular volume of a wellbore
Hermes, Robert E.; Gonzalez, Manuel E.; Llewellyn, Brian C.; Bloys, James B.
2010-06-29
A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.
Controlling the pressure within an annular volume of a wellbore
Hermes, Robert E.; Gonzalez, Manuel E.; Llewellyn, Brian C.; Bloys, James B.; Coates, Don M.
2011-05-31
A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.
Controlling the pressure within an annular volume of a wellbore
Hermes, Robert E.; Gonzalez, Manuel E.; Llewellyn, Brian C.; Bloys, James B.
2008-10-28
A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.
Controlling the pressure within an annular volume of a wellbore
Hermes, Robert E.; Gonzalez, Manuel E.; Llewellyn, Brian C.; Bloys, James B.
2011-01-18
A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.
Controlling the pressure within an annular volume of a wellbore
Hermes, Robert E.; Gonzalez, Manuel E.; Llewellyn, Brian C.; Bloys, James B.; Coates, Don M.
2011-06-21
A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.
75 FR 23582 - Annular Casing Pressure Management for Offshore Wells
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-04
... published the proposed rule Annular Casing Pressure Management for Offshore Wells (74 FR 38147). The comment... the published proposed rule 1010-AD47 Annular Casing Pressure Management for Offshore Wells (74 FR... subsea wellhead. (3) hybrid well, a riser or the production casing pressure is greater than 100...
Localized interstitial granuloma annulare induced by subcutaneous injections for desensitization.
Spring, Philipp; Vernez, Maxime; Maniu, Christa-Maria; Hohl, Daniel
2013-06-01
We describe a patient with interstitial granuloma annulare associated with subcutaneous injection therapy (SIT) for desensitization to a type I allergy. Asymptomatic, erythematous, violaceous annular patches were located at the injection sites on both her arms. Medical history revealed perennial rhinoconjonctivitis treated with SIT (Phostal Stallergen® cat 100% and D. pteronyssinus/D.farinae 50%:50%). PMID:24011321
Annular pancreas intra operatively discovered: a case report
Zeineb, Mzoughi; Sadri, Ben Abid; Nizar, Miloudi; Hassen, Hentati; Nafaa, Arfa; Taher, Khalfallah
2011-01-01
Annular pancreas is a rare congenital abnormality. This entity can rarely be symptomatic. Patients can present with gastrointestinal obstruction or acute pancreatitis. We report a case with a rich iconography, of an annular pancreas discovered intraoperatively. A 46-year-old woman was operated with the diagnosis of acute cholecystitis with common bile duct stones. At operation, a strip of pancreatic tissue (2 cm) completely encircled the second duodenum. Open cholecytectomy with choledocotomy and stones extractionwas done. Postoperatively, she developed an acute pancreatitis. The post-operative cholangiography showed the annular duct surrounding the second duodenum. Annular pancreas is rare. Symptoms may occur in newborn children. In adults, annular pancreas discovering is radiological or intra operatively. PMID:24765382
Virtual cathode microwave generator having annular anode slit
Kwan, T.J.T.; Snell, C.M.
1988-03-08
A microwave generator using an oscillating virtual cathode is described comprising: a cathode for emitting electrons; an anode for accelerating emitted electrons from the cathode, the anode having an annular slit therethrough effective for forming the virtual cathode and having at least one range thickness relative to electrons reflected from the virtual cathode; and magnet means for producing a magnetic field having a field strength effective to form an annular beam from the emitted electrons in substantial alignment with the annular anode slit and to enable the electrons reflected from the virtual cathode to axially diverge from the annular beam. The reflected electrons return toward the cathode diverge from the annular beam and are absorbed by the anode to substantially eliminate electrons reflexing between the cathode and the virtual cathode.
Accelerated Superposition State Molecular Dynamics for Condensed Phase Systems.
Ceotto, Michele; Ayton, Gary S; Voth, Gregory A
2008-04-01
An extension of superposition state molecular dynamics (SSMD) [Venkatnathan and Voth J. Chem. Theory Comput. 2005, 1, 36] is presented with the goal to accelerate timescales and enable the study of "long-time" phenomena for condensed phase systems. It does not require any a priori knowledge about final and transition state configurations, or specific topologies. The system is induced to explore new configurations by virtue of a fictitious (free-particle-like) accelerating potential. The acceleration method can be applied to all degrees of freedom in the system and can be applied to condensed phases and fluids. PMID:26620930
Scaling of macroscopic superpositions close to a quantum phase transition
NASA Astrophysics Data System (ADS)
Abad, Tahereh; Karimipour, Vahid
2016-05-01
It is well known that in a quantum phase transition (QPT), entanglement remains short ranged [Osterloh et al., Nature (London) 416, 608 (2005), 10.1038/416608a]. We ask if there is a quantum property entailing the whole system which diverges near this point. Using the recently proposed measures of quantum macroscopicity, we show that near a quantum critical point, it is the effective size of macroscopic superposition between the two symmetry breaking states which grows to the scale of system size, and its derivative with respect to the coupling shows both singular behavior and scaling properties.
Push-Pull Optical Pumping of Pure Superposition States
NASA Astrophysics Data System (ADS)
Jau, Y.-Y.; Miron, E.; Post, A. B.; Kuzma, N. N.; Happer, W.
2004-10-01
A new optical pumping method, “push-pull pumping,” can produce very nearly pure, coherent superposition states between the initial and the final sublevels of the important field-independent 0-0 clock resonance of alkali-metal atoms. The key requirement for push-pull pumping is the use of D1 resonant light which alternates between left and right circular polarization at the Bohr frequency of the state. The new pumping method works for a wide range of conditions, including atomic beams with almost no collisions, and atoms in buffer gases with pressures of many atmospheres.
Controllable photon bunching by atomic superpositions in a driven cavity
NASA Astrophysics Data System (ADS)
Guo, Weijie; Wang, Yao; Wei, L. F.
2016-04-01
We propose a feasible approach to generate the desired light with controllable photon bunchings by adjusting the atomic superpositions in a driven cavity. Under the large detuning limit, i.e., the cavity is far resonance with the inside atom(s), we show that the photons in the cavity are always bunchings. Typically, when the effective dispersive interaction equals the detuning between the driving and cavity fields, we find that the value of second-order correlation g(2 )(0 ) inverses to the probability of the superposed atomic state. This suggests that such a value could be arbitrarily large, and thus the bunchings of the photons could be significantly enhanced.
Effects study on the thermal stresses in a LEU metal foil annular target.
Govindarajan, Srisharan G; Solbrekken, Gary L
2015-09-01
The effects of fission gas pressure, uranium swelling and thermal contact conductance on the thermal-mechanical behavior of an annular target containing a low-enriched uranium foil (LEU) encapsulated in a nickel foil have been presented in this paper. The draw-plug assembly method is simulated to obtain the residual stresses, which are applied to the irradiation model as initial inputs, and the integrated assembly-irradiation process is simulated as an axisymmetric problem using the commercial finite element code Abaqus FEA. Parametric studies were performed on the LEU heat generation rate and the results indicate satisfactory irradiation performance of the annular target. The temperature and stress margins have been provided along with a discussion of the results. PMID:26036440
The liquid annular reactor system (LARS) propulsion
Maise, G.; Lazareth, O.W.; Horn, F.; Powell, J.R.; Ludewig, H. ); Lenard, R.X. )
1991-01-05
A new concept for very high specific impulse ({gt}2000 seconds) direct nuclear propulsion is described. The concept, termed LARS (Liquid Annular Reactor System) uses liquid nuclear fuel elements to heat hydrogen propellant to very high temperatures ({similar to}6000 K). Operating pressure is moderate ({similar to}10 atm), with the result that the outlet hydrogen is virtually 100% dissociated to monatomic H. The molten fuel is contained in a solid container of its own material, which is rotated to stabilize the liquid layer by centripetal force. LARS reactor designs are described, together with neutronic and thermal-hydraulic analyses. Power levels are on the order of 200 megawatts. Typically, LARS designs use 7 rotating fuel elements, are beryllium moderated and have critical radii of {similar to}100 cm (core L/D{approx}1.5).
Intraorbital granuloma annulare in an elderly patient.
Barrett, Dianne; Petris, Carisa; Garrido Hermosilla, Antonio Manuel; Oktavec, Kathleen; Mansukhani, Mahesh; Kazim, Michael
2016-06-01
Classically, granuloma annulare (GA) is a cutaneous disorder localized to the dorsum of the hands and/or feet in children and young adults. Very rarely it can present on the face and rarer still on periorbital structures such as the eyelid and orbital rim. Diagnosis hinges on clinical presentation and histological features, such as palisading granulomas with central destruction of collagen, presence of mucin and lymphohistiocytic infiltration. The etiology of this condition remains unknown, but may involve a delayed-type hypersensitivity reaction, malignancy and/or infection. Herein is the first reported case of an intraorbital GA in an 86-year-old male patient who presented with right eye proptosis. PMID:27163779
Annular array and method of manufacturing same
Day, Robert A.
1989-01-01
A method for manufacturing an annular acoustic transducer array from a plate of transducer material, which enables production of precision aligned arrays at low cost. The circular plate is sawed along at least two lines that are radial to the axis of the plate. At steps along each radial cut, the plate is rotated first in one direction and then in an opposite direction by a predetermined angle such as slightly less than 90.degree.. The cuts result in the forming of several largely ring-shaped lands, each largely ring-shaped land being joined to the other rings of different radii by thin portions of the plate, and each ring being cut into segments. The bridges that join different rings, hold the transducer together until it can be mounted on a lens.
Facility modernization Annular Core Research Reactor
Morris, F.M.; Luera, T.F.; McCrory, F.M.; Nelson, D.A.; Trowbridge, F.R.; Wold, S.A.
1990-07-01
The Annular Core Research Reactor (ACRR) has undergone numerous modifications since its conception in response to program needs. The original reactor fuel, which was special U-ZrH TRIGA fuel designed primarily for pulsing, has been replaced with a higher pulsing capacity BeO fuel. Other advanced operating modes which use this increased capability, in addition to the pulse and steady state, have been incorporated to tailor power histories and fluences to the experiments. Various experimental facilities have been developed that range from a radiography facility to a 50 cm diameter External Fuel Ring Cavity (FREC) using 180 of the original ZrH fuel elements. Currently a digital reactor console is being produced with GA, which will give enhanced monitoring capabilities of the reactor parameters while leaving the safety-related shutdown functions with analog technology. (author)
A Bethe ansatz solvable model for superpositions of Cooper pairs and condensed molecular bosons
NASA Astrophysics Data System (ADS)
Hibberd, K. E.; Dunning, C.; Links, J.
2006-08-01
We introduce a general Hamiltonian describing coherent superpositions of Cooper pairs and condensed molecular bosons. For particular choices of the coupling parameters, the model is integrable. One integrable manifold, as well as the Bethe ansatz solution, was found by Dukelsky et al. [J. Dukelsky, G.G. Dussel, C. Esebbag, S. Pittel, Phys. Rev. Lett. 93 (2004) 050403]. Here we show that there is a second integrable manifold, established using the boundary quantum inverse scattering method. In this manner we obtain the exact solution by means of the algebraic Bethe ansatz. In the case where the Cooper pair energies are degenerate we examine the relationship between the spectrum of these integrable Hamiltonians and the quasi-exactly solvable spectrum of particular Schrödinger operators. For the solution we derive here the potential of the Schrödinger operator is given in terms of hyperbolic functions. For the solution derived by Dukelsky et al., loc. cit. the potential is sextic and the wavefunctions obey PT-symmetric boundary conditions. This latter case provides a novel example of an integrable Hermitian Hamiltonian acting on a Fock space whose states map into a Hilbert space of PT-symmetric wavefunctions defined on a contour in the complex plane.
Recurrent Annular Peripheral Choroidal Detachment after Trabeculectomy
Liu, Shaohui; Sun, Lisa L.; Kavanaugh, A. Scott; Langford, Marlyn P.; Liang, Chanping
2013-01-01
We report a challenging case of recurrent flat anterior chamber without hypotony after trabeculectomy in a 54-year-old Black male with a remote history of steroid-treated polymyositis, cataract surgery, and uncontrolled open angle glaucoma. The patient presented with a flat chamber on postoperative day 11, but had a normal fundus exam and intraocular pressure (IOP). Flat chamber persisted despite treatment with cycloplegics, steroids, and a Healon injection into the anterior chamber. A transverse B-scan of the peripheral fundus revealed a shallow annular peripheral choroidal detachment. The suprachoroidal fluid was drained. The patient presented 3 days later with a recurrent flat chamber and an annular peripheral choroidal effusion. The fluid was removed and reinforcement of the scleral flap was performed with the resolution of the flat anterior chamber. A large corneal epithelial defect developed after the second drainage. The oral prednisone was tapered quickly and the topical steroid was decreased. One week later, his vision decreased to count fingers with severe corneal stromal edema and Descemet's membrane folds that improved to 20/50 within 24 h of resumption of the oral steroid and frequent topical steroid. The patient's visual acuity improved to 20/20 following a slow withdrawal of the oral and topical steroid. Eight months after surgery, the IOP was 15 mm Hg without glaucoma medication. The detection of a shallow anterior choroidal detachment by transverse B-scan is critical to making the correct diagnosis. Severe cornea edema can occur if the steroid is withdrawn too quickly. Thus, steroids should be tapered cautiously in steroid-dependent patients. PMID:24348402
A millimeter wave linear superposition oscillator in 0.18 μm CMOS technology
NASA Astrophysics Data System (ADS)
Dong, Yan; Luhong, Mao; Qiujie, Su; Sheng, Xie; Shilin, Zhang
2014-01-01
This paper presents a millimeter wave (mm-wave) oscillator that generates signal at 36.56 GHz. The mm-wave oscillator is realized in a UMC 0.18 μm CMOS process. The linear superposition (LS) technique breaks through the limit of cut-off frequency (fT), and realizes a much higher oscillation than fT. Measurement results show that the LS oscillator produces a calibrated -37.17 dBm output power when biased at 1.8 V; the output power of fundamental signal is -10.85 dBm after calibration. The measured phase noise at 1 MHz frequency offset is -112.54 dBc/Hz at the frequency of 9.14 GHz. This circuit can be properly applied to mm-wave communication systems with advantages of low cost and high integration density.
Evolution of superpositions of quantum states through a level crossing
Torosov, B. T.; Vitanov, N. V.
2011-12-15
The Landau-Zener-Stueckelberg-Majorana (LZSM) model is widely used for estimating transition probabilities in the presence of crossing energy levels in quantum physics. This model, however, makes the unphysical assumption of an infinitely long constant interaction, which introduces a divergent phase in the propagator. This divergence remains hidden when estimating output probabilities for a single input state insofar as the divergent phase cancels out. In this paper we show that, because of this divergent phase, the LZSM model is inadequate to describe the evolution of pure or mixed superposition states across a level crossing. The LZSM model can be used only if the system is initially in a single state or in a completely mixed superposition state. To this end, we show that the more realistic Demkov-Kunike model, which assumes a hyperbolic-tangent level crossing and a hyperbolic-secant interaction envelope, is free of divergences and is a much more adequate tool for describing the evolution through a level crossing for an arbitrary input state. For multiple crossing energies which are reducible to one or more effective two-state systems (e.g., by the Majorana and Morris-Shore decompositions), similar conclusions apply: the LZSM model does not produce definite values of the populations and the coherences, and one should use the Demkov-Kunike model instead.
Experiments testing macroscopic quantum superpositions must be slow.
Mari, Andrea; De Palma, Giacomo; Giovannetti, Vittorio
2016-01-01
We consider a thought experiment where the preparation of a macroscopically massive or charged particle in a quantum superposition and the associated dynamics of a distant test particle apparently allow for superluminal communication. We give a solution to the paradox which is based on the following fundamental principle: any local experiment, discriminating a coherent superposition from an incoherent statistical mixture, necessarily requires a minimum time proportional to the mass (or charge) of the system. For a charged particle, we consider two examples of such experiments, and show that they are both consistent with the previous limitation. In the first, the measurement requires to accelerate the charge, that can entangle with the emitted photons. In the second, the limitation can be ascribed to the quantum vacuum fluctuations of the electromagnetic field. On the other hand, when applied to massive particles our result provides an indirect evidence for the existence of gravitational vacuum fluctuations and for the possibility of entangling a particle with quantum gravitational radiation. PMID:26959656
Experiments testing macroscopic quantum superpositions must be slow
NASA Astrophysics Data System (ADS)
Mari, Andrea; de Palma, Giacomo; Giovannetti, Vittorio
2016-03-01
We consider a thought experiment where the preparation of a macroscopically massive or charged particle in a quantum superposition and the associated dynamics of a distant test particle apparently allow for superluminal communication. We give a solution to the paradox which is based on the following fundamental principle: any local experiment, discriminating a coherent superposition from an incoherent statistical mixture, necessarily requires a minimum time proportional to the mass (or charge) of the system. For a charged particle, we consider two examples of such experiments, and show that they are both consistent with the previous limitation. In the first, the measurement requires to accelerate the charge, that can entangle with the emitted photons. In the second, the limitation can be ascribed to the quantum vacuum fluctuations of the electromagnetic field. On the other hand, when applied to massive particles our result provides an indirect evidence for the existence of gravitational vacuum fluctuations and for the possibility of entangling a particle with quantum gravitational radiation.
Modeling scattering from azimuthally symmetric bathymetric features using wavefield superposition.
Fawcett, John A
2007-12-01
In this paper, an approach for modeling the scattering from azimuthally symmetric bathymetric features is described. These features are useful models for small mounds and indentations on the seafloor at high frequencies and seamounts, shoals, and basins at low frequencies. A bathymetric feature can be considered as a compact closed region, with the same sound speed and density as one of the surrounding media. Using this approach, a number of numerical methods appropriate for a partially buried target or facet problem can be applied. This paper considers the use of wavefield superposition and because of the azimuthal symmetry, the three-dimensional solution to the scattering problem can be expressed as a Fourier sum of solutions to a set of two-dimensional scattering problems. In the case where the surrounding two half spaces have only a density contrast, a semianalytic coupled mode solution is derived. This provides a benchmark solution to scattering from a class of penetrable hemispherical bosses or indentations. The details and problems of the numerical implementation of the wavefield superposition method are described. Example computations using the method for a simple scattering feature on a seabed are presented for a wide band of frequencies. PMID:18247740
Experiments testing macroscopic quantum superpositions must be slow
Mari, Andrea; De Palma, Giacomo; Giovannetti, Vittorio
2016-01-01
We consider a thought experiment where the preparation of a macroscopically massive or charged particle in a quantum superposition and the associated dynamics of a distant test particle apparently allow for superluminal communication. We give a solution to the paradox which is based on the following fundamental principle: any local experiment, discriminating a coherent superposition from an incoherent statistical mixture, necessarily requires a minimum time proportional to the mass (or charge) of the system. For a charged particle, we consider two examples of such experiments, and show that they are both consistent with the previous limitation. In the first, the measurement requires to accelerate the charge, that can entangle with the emitted photons. In the second, the limitation can be ascribed to the quantum vacuum fluctuations of the electromagnetic field. On the other hand, when applied to massive particles our result provides an indirect evidence for the existence of gravitational vacuum fluctuations and for the possibility of entangling a particle with quantum gravitational radiation. PMID:26959656
Runs in superpositions of renewal processes with applications to discrimination
NASA Astrophysics Data System (ADS)
Alsmeyer, Gerold; Irle, Albrecht
2006-02-01
Wald and Wolfowitz [Ann. Math. Statist. 11 (1940) 147-162] introduced the run test for testing whether two samples of i.i.d. random variables follow the same distribution. Here a run means a consecutive subsequence of maximal length from only one of the two samples. In this paper we contribute to the problem of runs and resulting test procedures for the superposition of independent renewal processes which may be interpreted as arrival processes of customers from two different input channels at the same service station. To be more precise, let (Sn)n[greater-or-equal, slanted]1 and (Tn)n[greater-or-equal, slanted]1 be the arrival processes for channel 1 and channel 2, respectively, and (Wn)n[greater-or-equal, slanted]1 their be superposition with counting process . Let further be the number of runs in W1,...,Wn and the number of runs observed up to time t. We study the asymptotic behavior of and Rt, first for the case where (Sn)n[greater-or-equal, slanted]1 and (Tn)n[greater-or-equal, slanted]1 have exponentially distributed increments with parameters [lambda]1 and [lambda]2, and then for the more difficult situation when these increments have an absolutely continuous distribution. These results are used to design asymptotic level [alpha] tests for testing [lambda]1=[lambda]2 against [lambda]1[not equal to][lambda]2 in the first case, and for testing for equal scale parameters in the second.
Vanierschot, Maarten; Van den Bulck, Eric
2008-01-01
In this paper the static pressure field of an annular swirling jet is measured indirectly using stereo-PIV measurements. The pressure field is obtained from numerically solving the Poisson equation, taken into account the axisymmetry of the flow At the boundaries no assumptions are made and the exact boundary conditions are applied. Since all source terms can be measured using stereo-PIV and the boundary conditions are exact, no assumptions other than axisymmetry had to be made in the calculation of the pressure field. The advantage of this method of indirect pressure measurement is its high spatial resolution compared to the traditional pitot probes. Moreover this method is non-intrusive while the insertion of a pitot tube disturbs the flow It is shown that the annular swirling flow can be divided into three regimes: a low, an intermediate and a high swirling regime. The pressure field of the low swirling regime is the superposition of the pressure field of the non-swirling jet and a swirl induced pressure field due to the centrifugal forces of the rotating jet. As the swirl increases, the swirl induced pressure field becomes dominant and for the intermediate and high swirling regimes, the simple radial equilibrium equation holds.
Student ability to distinguish between superposition states and mixed states in quantum mechanics
NASA Astrophysics Data System (ADS)
Passante, Gina; Emigh, Paul J.; Shaffer, Peter S.
2015-12-01
Superposition gives rise to the probabilistic nature of quantum mechanics and is therefore one of the concepts at the heart of quantum mechanics. Although we have found that many students can successfully use the idea of superposition to calculate the probabilities of different measurement outcomes, they are often unable to identify the experimental implications of a superposition state. In particular, they fail to recognize how a superposition state and a mixed state (sometimes called a "lack of knowledge" state) can produce different experimental results. We present data that suggest that superposition in quantum mechanics is a difficult concept for students enrolled in sophomore-, junior-, and graduate-level quantum mechanics courses. We illustrate how an interactive lecture tutorial can improve student understanding of quantum mechanical superposition. A longitudinal study suggests that the impact persists after an additional quarter of quantum mechanics instruction that does not specifically address these ideas.
NASA Astrophysics Data System (ADS)
Niu, X. Y.; Huang, X. L.; Shang, Y. F.; Wang, X. Y.
2015-04-01
Superposition principle plays a crucial role in quantum mechanics, thus its effects on thermodynamics is an interesting topic. Here, the effects of superpositions of quantum states on isoenergetic cycle are studied. We find superposition can improve the heat engine efficiency and release the positive work condition in general case. In the finite time process, we find the efficiency at maximum power output in superposition case is lower than the nonsuperposition case. This efficiency depends on one index of the energy spectrum of the working substance. This result does not mean the superposition discourages the heat engine performance. For fixed efficiency or fixed power, the superposition improves the power or efficiency respectively. These results show how quantum mechanical properties affect the thermodynamical cycle.
The origin of non-classical effects in a one-dimensional superposition of coherent states
NASA Technical Reports Server (NTRS)
Buzek, V.; Knight, P. L.; Barranco, A. Vidiella
1992-01-01
We investigate the nature of the quantum fluctuations in a light field created by the superposition of coherent fields. We give a physical explanation (in terms of Wigner functions and phase-space interference) why the 1-D superposition of coherent states in the direction of the x-quadrature leads to the squeezing of fluctuations in the y-direction, and show that such a superposition can generate the squeezed vacuum and squeezed coherent states.
Robustness of superposition states evolving under the influence of a thermal reservoir
Sales, J. S.; Almeida, N. G. de
2011-06-15
We study the evolution of superposition states under the influence of a reservoir at zero and finite temperatures in cavity quantum electrodynamics aiming to know how their purity is lost over time. The superpositions studied here are composed of coherent states, orthogonal coherent states, squeezed coherent states, and orthogonal squeezed coherent states, which we introduce to generalize the orthogonal coherent states. For comparison, we also show how the robustness of the superpositions studied here differs from that of a qubit given by a superposition of zero- and one-photon states.
Macroscopicity of quantum superpositions on a one-parameter unitary path in Hilbert space
NASA Astrophysics Data System (ADS)
Volkoff, T. J.; Whaley, K. B.
2014-12-01
We analyze quantum states formed as superpositions of an initial pure product state and its image under local unitary evolution, using two measurement-based measures of superposition size: one based on the optimal quantum binary distinguishability of the branches of the superposition and another based on the ratio of the maximal quantum Fisher information of the superposition to that of its branches, i.e., the relative metrological usefulness of the superposition. A general formula for the effective sizes of these states according to the branch-distinguishability measure is obtained and applied to superposition states of N quantum harmonic oscillators composed of Gaussian branches. Considering optimal distinguishability of pure states on a time-evolution path leads naturally to a notion of distinguishability time that generalizes the well-known orthogonalization times of Mandelstam and Tamm and Margolus and Levitin. We further show that the distinguishability time provides a compact operational expression for the superposition size measure based on the relative quantum Fisher information. By restricting the maximization procedure in the definition of this measure to an appropriate algebra of observables, we show that the superposition size of, e.g., NOON states and hierarchical cat states, can scale linearly with the number of elementary particles comprising the superposition state, implying precision scaling inversely with the total number of photons when these states are employed as probes in quantum parameter estimation of a 1-local Hamiltonian in this algebra.
Wall pressure measurements of flooding in vertical countercurrent annular air–water flow
Choutapalli, I., Vierow, K.
2010-01-01
An experimental study of flooding in countercurrent air-water annular flow in a large diameter vertical tube using wall pressure measurements is described in this paper. Axial pressure profiles along the length of the test section were measured up to and after flooding using fast response pressure transducers for three representative liquid flow rates representing a wide range of liquid Reynolds numbers (ReL = 4Γ/μ; Γ is the liquid mass flow rate per unit perimeter; μ is the dynamic viscosity) from 3341 to 19,048. The results show that flooding in large diameter tubes cannot be initiated near the air outlet and is only initiated near the air inlet. Fourier analysis of the wall pressure measurements shows that up to the point of flooding, there is no dominant wave frequency but rather a band of frequencies encompassing both the low frequency and the broad band that are responsible for flooding. The data indicates that flooding in large diameter vertical tubes may be caused by the constructive superposition of a plurality of waves rather than the action of a single large-amplitude wave.
Pollution technology program, can-annular combustor engines
NASA Technical Reports Server (NTRS)
Roberts, R.; Fiorentino, A. J.; Greene, W.
1976-01-01
A Pollution Reduction Technology Program to develop and demonstrate the combustor technology necessary to reduce exhaust emissions for aircraft engines using can-annular combustors is described. The program consisted of design, fabrication, experimental rig testing and assessment of results and was conducted in three program elements. The combustor configurations of each program element represented increasing potential for meeting the 1979 Environmental Protection Agency (EPA) emission standards, while also representing increasing complexity and difficulty of development and adaptation to an operational engine. Experimental test rig results indicate that significant reductions were made to the emission levels of the baseline JT8D-17 combustor by concepts in all three program elements. One of the Element I single-stage combustors reduced carbon monoxide to a level near, and total unburned hydrocarbons (THC) and smoke to levels below the 1979 EPA standards with little or no improvement in oxides of nitrogen. The Element II two-stage advanced Vorbix (vortex burning and mixing) concept met the standard for THC and achieved significant reductions in CO and NOx relative to the baseline. Although the Element III prevaporized-premixed concept reduced high power NOx below the Element II results, there was no improvement to the integrated EPA parameter relative to the Vorbix combustor.
Ni, Haibin; Wang, Ming; Shen, Tianyi; Zhou, Jing
2015-02-24
Surface plasmons that propagate along cylindrical metal/dielectric interfaces in annular apertures in metal films, called cylindrical surface plasmons (CSPs), exhibit attractive optical characteristics. However, it is challenging to fabricate these nanocoaxial structures. Here, we demonstrate a practical low-cost route to manufacture highly ordered, large-area annular cavity arrays (ACAs) that can support CSPs with great tunability. By employing a sol-gel coassembly method, reactive ion etching and metal sputtering techniques, regular, highly ordered ACAs in square-centimeter-scale with a gap width tunable in the range of several to hundreds of nanometers have been produced with good reproducibility. Ag ACAs with a gap width of 12 nm and a gap height of 635 nm are demonstrated. By finite-difference time-domain simulation, we confirm that the pronounced dips in the reflectance spectra of ACAs are attributable to CSP resonances excited in the annular gaps. By adjusting etching time and Ag film thickness, the CSP dips can be tuned to sweep the entire optical range of 360 to 1800 nm without changing sphere size, which makes them a promising candidate for forming integrated plasmonic sensing arrays. The high tunability of the CSP resonant frequencies together with strong electric field enhancement in the cavities make the ACAs promising candidates for surface plasmon sensors and SERS substrates, as, for example, they have been used in liquid refractive index (RI) sensing, demonstrating a sensitivity of 1505 nm/RIU and a figure of merit of 9. One of the CSP dips of ACAs with a certain geometry size is angle- (0-70 degrees) and polarization-independent and can be used as a narrow-band absorber. Furthermore, the nano annular cavity arrays can be used to construct solar cells, nanolasers and nanoparticle plasmonic tweezers. PMID:25639937
Superposition method for analysis of free-edge stresses
NASA Technical Reports Server (NTRS)
Whitcomb, J. D.; Raju, I. S.
1983-01-01
Superposition techniques were used to transform the edge stress problem for composite laminates into a more lucid form. By eliminating loads and stresses not contributing to interlaminar stresses, the essential aspects of the edge stress problem are easily recognized. Transformed problem statements were developed for both mechanical and thermal loads. Also, a technique for approximate analysis using a two dimensional plane strain analysis was developed. Conventional quasi-three dimensional analysis was used to evaluate the accuracy of the transformed problems and the approximate two dimensional analysis. The transformed problems were shown to be exactly equivalent to the original problems. The approximate two dimensional analysis was found to predict the interlaminar normal and shear stresses reasonably well.
Sensing Super-Position: Human Sensing Beyond the Visual Spectrum
NASA Technical Reports Server (NTRS)
Maluf, David A.; Schipper, John F.
2007-01-01
The coming decade of fast, cheap and miniaturized electronics and sensory devices opens new pathways for the development of sophisticated equipment to overcome limitations of the human senses. This paper addresses the technical feasibility of augmenting human vision through Sensing Super-position by mixing natural Human sensing. The current implementation of the device translates visual and other passive or active sensory instruments into sounds, which become relevant when the visual resolution is insufficient for very difficult and particular sensing tasks. A successful Sensing Super-position meets many human and pilot vehicle system requirements. The system can be further developed into cheap, portable, and low power taking into account the limited capabilities of the human user as well as the typical characteristics of his dynamic environment. The system operates in real time, giving the desired information for the particular augmented sensing tasks. The Sensing Super-position device increases the image resolution perception and is obtained via an auditory representation as well as the visual representation. Auditory mapping is performed to distribute an image in time. The three-dimensional spatial brightness and multi-spectral maps of a sensed image are processed using real-time image processing techniques (e.g. histogram normalization) and transformed into a two-dimensional map of an audio signal as a function of frequency and time. This paper details the approach of developing Sensing Super-position systems as a way to augment the human vision system by exploiting the capabilities of Lie human hearing system as an additional neural input. The human hearing system is capable of learning to process and interpret extremely complicated and rapidly changing auditory patterns. The known capabilities of the human hearing system to learn and understand complicated auditory patterns provided the basic motivation for developing an image-to-sound mapping system. The
Superresolved imaging in digital holography by superposition of tilted wavefronts.
Mico, Vicente; Zalevsky, Zeev; García-Martínez, Pascuala; García, Javier
2006-02-10
A technique based on superresolution by digital holographic microscopic imaging is presented. We used a two dimensional (2-D) vertical-cavity self-emitting laser (VCSEL) array as spherical-wave illumination sources. The method is defined in terms of an incoherent superposition of tilted wavefronts. The tilted spherical wave originating from the 2-D VCSEL elements illuminates the target in transmission mode to obtain a hologram in a Mach-Zehnder interferometer configuration. Superresolved images of the input object above the common lens diffraction limit are generated by sequential recording of the individual holograms and numerical reconstruction of the image with the extended spatial frequency range. We have experimentally tested the approach for a microscope objective with an exact 2-D reconstruction image of the input object. The proposed approach has implementation advantages for applications in biological imaging or the microelectronic industry in which structured targets are being inspected. PMID:16512523
Spatial properties of coaxial superposition of two coherent Gaussian beams.
Boubaha, Boualem; Naidoo, Darryl; Godin, Thomas; Fromager, Michael; Forbes, Andrew; Aït-Ameur, Kamel
2013-08-10
In this paper, we explore theoretically and experimentally the laser beam shaping ability resulting from the coaxial superposition of two coherent Gaussian beams (GBs). This technique is classified under interferometric laser beam shaping techniques contrasting with the usual ones based on diffraction. The experimental setup does not involve the use of some two-wave interferometer but uses a spatial light modulator for the generation of the necessary interference term. This allows one to avoid the thermal drift occurring in interferometers and gives a total flexibility of the key parameter setting the beam transformation. In particular, we demonstrate the reshaping of a GB into a bottle beam or top-hat beam in the focal plane of a focusing lens. PMID:23938430
Principle of radial transport in low temperature annular plasmas
Zhang, Yunchao Charles, Christine; Boswell, Rod
2015-07-15
Radial transport in low temperature annular plasmas is investigated theoretically in this paper. The electrons are assumed to be in quasi-equilibrium due to their high temperature and light inertial mass. The ions are not in equilibrium and their transport is analyzed in three different situations: a low electric field (LEF) model, an intermediate electric field (IEF) model, and a high electric field (HEF) model. The universal IEF model smoothly connects the LEF and HEF models at their respective electric field strength limits and gives more accurate results of the ion mobility coefficient and effective ion temperature over the entire electric field strength range. Annular modelling is applied to an argon plasma and numerical results of the density peak position, the annular boundary loss coefficient and the electron temperature are given as functions of the annular geometry ratio and Paschen number.
Virtual cathode microwave generator having annular anode slit
Kwan, Thomas J. T.; Snell, Charles M.
1988-01-01
A microwave generator is provided for generating microwaves substantially from virtual cathode oscillation. Electrons are emitted from a cathode and accelerated to an anode which is spaced apart from the cathode. The anode has an annular slit therethrough effective to form the virtual cathode. The anode is at least one range thickness relative to electrons reflecting from the virtual cathode. A magnet is provided to produce an optimum magnetic field having the field strength effective to form an annular beam from the emitted electrons in substantial alignment with the annular anode slit. The magnetic field, however, does permit the reflected electrons to axially diverge from the annular beam. The reflected electrons are absorbed by the anode in returning to the real cathode, such that substantially no reflexing electrons occur. The resulting microwaves are produced with a single dominant mode and are substantially monochromatic relative to conventional virtual cathode microwave generators.
A wave superposition method formulated in digital acoustic space
NASA Astrophysics Data System (ADS)
Hwang, Yong-Sin
In this thesis, a new formulation of the Wave Superposition method is proposed wherein the conventional mesh approach is replaced by a simple 3-D digital work space that easily accommodates shape optimization for minimizing or maximizing radiation efficiency. As sound quality is in demand in almost all product designs and also because of fierce competition between product manufacturers, faster and accurate computational method for shape optimization is always desired. Because the conventional Wave Superposition method relies solely on mesh geometry, it cannot accommodate fast shape changes in the design stage of a consumer product or machinery, where many iterations of shape changes are required. Since the use of a mesh hinders easy shape changes, a new approach for representing geometry is introduced by constructing a uniform lattice in a 3-D digital work space. A voxel (a portmanteau, a new word made from combining the sound and meaning, of the words, volumetric and pixel) is essentially a volume element defined by the uniform lattice, and does not require separate connectivity information as a mesh element does. In the presented method, geometry is represented with voxels that can easily adapt to shape changes, therefore it is more suitable for shape optimization. The new method was validated by computing radiated sound power of structures of simple and complex geometries and complex mode shapes. It was shown that matching volume velocity is a key component to an accurate analysis. A sensitivity study showed that it required at least 6 elements per acoustic wavelength, and a complexity study showed a minimal reduction in computational time.
Annular elastolytic giant cell granuloma: A report of 10 cases
Arora, Sandeep; Malik, Ajay; Patil, Chetan; Balki, Anil
2015-01-01
Annular elastolytic giant cell granuloma initially described by O’Brien in 1975 is a disorder of uncertain etiopathogenesis presenting with annular erythematous plaques predominantly on the sun-exposed areas. Hisptopathologically, it is characterized by elastin degenration, multinucleate giant cells, and elastophagocytosis. The authors came across 10 such cases, which were managed with hydroxychloroquine resulting in complete resolution in 4–6 months. PMID:26904442
Annular Arrays Of Solar Cells For Spinning Spacecraft
NASA Technical Reports Server (NTRS)
Spilker, Thomas R.
1995-01-01
Report proposes annular arrays of solar photovoltaic cells installed on spin-stabilized spacecraft. Annular array faces Sun. Typical array consists of two stacked annuli of solar cells: one annulus fixed about spin axis, while other divided into deployable sectors mounted on dual swing arms and stowed by folding them atop fixed annulus. Once released, deployable sectors swing outward under spring or centrifugal force and expose fixed array so it generates additional power.
Experimental Results for an Annular Aerospike with Differential Throttling
NASA Technical Reports Server (NTRS)
Ruf, Joseph H.; McDaniels, David M.
2005-01-01
A) MSFC funded an internal study on Altitude Compensating Nozzles: 1) Develop an ACN design and performance prediction tool. 2) Design, build and test cold flow ACN nozzles. 3) An annular aerospike nozzle was designed and tested. 4) Incorporated differential throttling to assess Thrust Vector Control. B) Objective of the test hardware: 1) Provide design tool verification. 2) Provide benchmark data for CFD calculations. 3) Experimentally measure side force, or TVC, for a differentially throttled annular aerospike.
Skov, Søren Nielsen; Røpcke, Diana Mathilde; Ilkjær, Christine; Rasmussen, Jonas; Tjørnild, Marcell Juan; Jimenez, Jorge H; Yoganathan, Ajit P; Nygaard, Hans; Nielsen, Sten Lyager; Jensen, Morten Olgaard
2016-03-21
Limited knowledge exists about the forces acting on mitral valve annuloplasty repair devices. The aim of this study was to develop a new mitral annular force transducer to measure the forces acting on clinically used mitral valve annuloplasty devices. The design of an X-shaped transducer in the present study was optimized for simultaneous in- and out-of-plane force measurements. Each arm was mounted with strain gauges on four circumferential elements to measure out-of-plane forces, and the central parts of the X-arms were mounted with two strain gauges to measure in-plane forces. A dedicated calibration setup was developed to calibrate isolated forces with tension and compression for in- and out-of-plane measurements. With this setup, it was possible with linear equations to isolate and distinguish measured forces between the two planes and minimize transducer arm crosstalk. An in-vitro test was performed to verify the crosstalk elimination method and the assumptions behind it. The force transducer was implanted and evaluated in an 80kg porcine in-vivo model. Following crosstalk elimination, in-plane systolic force accumulation was found to be in average 4.0±0.1N and the out-of-plane annular segments experienced an average force of 1.4±0.4N. Directions of the systolic out-of-plane forces indicated movements towards a saddle shaped annulus, and the transducer was able to measure independent directional forces in individual annular segments. Further measurements with the new transducer coupled with clinical annuloplasty rings will provide a detailed insight into the biomechanical dynamics of these devices. PMID:26903412
Solar cycle modulation of Southern Annular Mode
NASA Astrophysics Data System (ADS)
Kuroda, Yuhji
2016-04-01
Climate is known to be affected by various factors, including oceanic changes and volcanic eruptions. 11-year solar cycle change is one of such important factors. Observational analysis shows that the winter-mean North Atlantic Oscillation (NAO) and late-winter/spring Southern Annular Mode (SAM) show structural modulation associated with 11-year solar cycle. In fact, these signals tend to extend from surface to upper stratosphere and persistent longer period only in the High Solar (HS) years. In the present study, we used 35-year record of ERA-Interim reanalysis data and performed wave-energy and momentum analysis on the solar-cycle modulation of the SAM to examine key factors to create such solar-SAM relationship. It is found that enhanced wave-mean flow interaction tends to take place in the middle stratosphere in association with enhanced energy input from diabatic heating on September only in HS years. The result suggests atmospheric and solar conditions on September are keys to create solar-SAM relationship.
Experiment of rocket-ram annular combustor
NASA Astrophysics Data System (ADS)
Yatsuyanagi, Nobuyuki; Sakamoto, Hiroshi; Sato, Kazuo; Sasaki, Masaki; Ono, Fumiei
Superiority in specific impulse of the double-nozzle type of rocket-ram combined engine over the ducted type of combined engine was shown by performance calculations. Then, a double-nozzle type of rocket-ram annular combustor with a total thrust of 5 kN was designed and experimentally tested with varying ratios of thrust produced by rocket and ram. With the combustor having different diverging half-angles, namely 10 deg 18 arcmin, and 6 deg 40 arcmin, thrust and pressure distribution along the common expansion nozzle were measured to investigate the effect of interaction of the two expansion gases on thrust. Enhancement of specific impulse was experimentally verified. That is, the specific impulse gained in rocket-ram parallel operations, the ratio of rocket thrust to ram thrust being 50 to 50, were found to be 190 percent of those in pure rocket operations. However, in the downstream region of the common nozzle, the flow might separate due to the generation of shock waves in either type of nozzle configuration.
Mechanical properties of stapedial annular ligament.
Gan, Rong Z; Yang, Fan; Zhang, Xiangming; Nakmali, Don
2011-04-01
Stapedial annular ligament (SAL) provides a sealed but mobile boundary between the stapes footplate and oval window bony wall. Mechanical properties of the SAL affect the transmission of ossicular movement into the cochlea in sound conduction. However, the mechanical properties of this tissue have never been investigated due to its complexity. In this paper, we report measurement of the viscoelastic properties of SAL on human cadaver temporal bones using a micro-material testing system with digital image correlation analysis. The measured load-deformation relations of SAL samples were converted into shear stress-shear strain relationship, stress relaxation function, and ultimate shear stress and shear strain of the SAL. The hyperelastic Ogden model was used to describe constitutive behavior of the SAL and a 3D finite element model of the experimental setup with SAL was created for assessing the effects of loading variation and measurement errors on results. The study demonstrates that the human SAL is a typical viscoelastic material with hysteresis, nonlinear stress-strain relationship and stress relaxation function. The shear modulus changes from 3.6 to 220 kPa when the shear stress increases from 2 to 140 kPa. These results provide useful information on quasi-static behavior of the SAL. PMID:21112232
Simulation of cryogenic turbopump annular seals
NASA Astrophysics Data System (ADS)
Palazzolo, Alan B.
1993-11-01
San Andres employed the NBS software package MIPROPS to account for density's dependence on pressure in the simulation of liquid annular seals. His example on a LH2 seal showed a significant change in the mass coefficient compared to a constant density model. San Andres, Yang, and Childs extended this analysis by including the pressure and temperature dependence of density, specific heat, viscosity, volumetric expansion, and thermal conductivity in a coupled solution of the energy, momentum, and continuity equations. Their example showed very significant changes in stiffness and inertia for a high speed (38,000 rpm), large L/D ratio (0.5) LOX seal, as compared to their constant temperature results. The current research rederived the San Andres-Yang-Childs (SYC) analysis and extended it to include not only the Moody friction model of SYC but also the Hir's friction model. The derivation begins with obtaining the local differential equations of continuity, momentum, and energy conservation in the seal. These equations are averaged across the film thickness to obtain the resulting 'bulk flow' differential equations. Shear stress and convective heat loss through the stator (seal) and rotor are related to the Moody and Hir's friction factor model. The Holman analogy is employed to relate heat conduction in or out of the fluid film's boundary layer to the friction induced shear stress.
Fluxon Dynamics in Elliptic Annular Josephson Junctions
NASA Astrophysics Data System (ADS)
Monaco, Roberto; Mygind, Jesper
2016-04-01
We analyze the dynamics of a magnetic flux quantum (current vortex) trapped in a current-biased long planar elliptic annular Josephson tunnel junction. The system is modeled by a perturbed sine-Gordon equation that determines the spatial and temporal behavior of the phase difference across the tunnel barrier separating the two superconducting electrodes. In the absence of an external magnetic field, the fluxon dynamics in an elliptic annulus does not differ from that of a circular annulus where the stationary fluxon speed merely is determined by the system losses. The interaction between the vortex magnetic moment and a spatially homogeneous in-plane magnetic field gives rise to a tunable periodic non-sinusoidal potential which is strongly dependent on the annulus aspect ratio. We study the escape of the vortex from a well in the tilted potential when the bias current exceeds the depinning current. The smallest depinning current as well as the lowest sensitivity of the annulus to the external field is achieved when the axes ratio is equal to √{2}. The presented extensive numerical results are in good agreement with the findings of the perturbative approach. We also probe the rectifying properties of an asymmetric potential implemented with an egg-shaped annulus formed by two semi-elliptic arcs.
Granuloma annulare: another manifestation of Bartonella infection?
Smoller, B R; Madhusudhan, K T; Scott, M A; Horn, T D
2001-12-01
Granuloma annulare (GA) is a common cutaneous eruption whose pathogenesis remains unknown. Recent literature has suggested a relation between Borrelia infection and GA, a relation that has not been widely accepted. Earlier works attempted unsuccessfully to implicate various other infectious agents. Some reports have demonstrated the increased frequency of GA in patients with human immunodeficiency virus infection, again raising the possibility of an infectious etiology. Using polymerase chain reaction amplification, we examined 19 biopsy specimens from 19 patients with GA (14 with classic palisading GA and 5 with an interstitial pattern) for the presence of a 153-base pair sequence specific for Bartonella henselae or Bartonella quintana. None of our patients were known to be human immunodeficiency virus-positive. These primers failed to detect B. henselae and B. quintana DNA in any of the specimens examined. Our findings do not support the hypothesis that GA represents a granulomatous reaction pattern to cutaneous Bartonella infection. Nevertheless, we cannot exclude the possibility that there may be a relation in other geographic locations or in immunocompromised patients or that GA represents an autosensitization reaction in response to a distant site of infection. Additional studies are needed to address these hypotheses. PMID:11801791
NASA Astrophysics Data System (ADS)
Sun, Shufeng; Wu, Yuyuan; Zhao, Rongyi
2001-04-01
According to a separated phase flow model for vertical annular two-phase flow in an annular channel, the liquid film thickness, distributions of velocities and temperatures in the liquid layer are predicted in the range of heat fluxes: 6000-12000 W/m 2, mass flux: 500-1100 kg/m2 s. The pressure drop along the flow channel and heat transfer coefficient are also calculated. The liquid film thickness is in the order of micrometers and heat transfer coefficient is 2800-7800 W/m2 K of liquid nitrogen boiling in narrow annular channels. The measured heat transfer coefficient is 29% higher than the calculated values. With the mass flux increasing and the gap of the annular channel decreasing, pressure drop and heat transfer coefficient increase.
Student Ability to Distinguish between Superposition States and Mixed States in Quantum Mechanics
ERIC Educational Resources Information Center
Passante, Gina; Emigh, Paul J.; Shaffer, Peter S.
2015-01-01
Superposition gives rise to the probabilistic nature of quantum mechanics and is therefore one of the concepts at the heart of quantum mechanics. Although we have found that many students can successfully use the idea of superposition to calculate the probabilities of different measurement outcomes, they are often unable to identify the…
Liu, Xiang; Chandrasekhar, S; Winzer, P J; Chraplyvy, A R; Tkach, R W; Zhu, B; Taunay, T F; Fishteyn, M; DiGiovanni, D J
2012-08-13
Coherent superposition of light waves has long been used in various fields of science, and recent advances in digital coherent detection and space-division multiplexing have enabled the coherent superposition of information-carrying optical signals to achieve better communication fidelity on amplified-spontaneous-noise limited communication links. However, fiber nonlinearity introduces highly correlated distortions on identical signals and diminishes the benefit of coherent superposition in nonlinear transmission regime. Here we experimentally demonstrate that through coordinated scrambling of signal constellations at the transmitter, together with appropriate unscrambling at the receiver, the full benefit of coherent superposition is retained in the nonlinear transmission regime of a space-diversity fiber link based on an innovatively engineered multi-core fiber. This scrambled coherent superposition may provide the flexibility of trading communication capacity for performance in future optical fiber networks, and may open new possibilities in high-performance and secure optical communications. PMID:23038549
Sea Carousel—A benthic, annular flume
NASA Astrophysics Data System (ADS)
Amos, Carl L.; Grant, J.; Daborn, G. R.; Black, K.
1992-06-01
A benthic annular flume (Sea Carousel) has been developed and tested to measure in situ the erodibility of cohesive sediments. The flume is equipped with three optical backscatter sensors, a lid rotation switch, and an electromagnetic (EM) flow meter capable of detecting azimuthal and vertical components of flow. Data are logged at rates up to 10·66 Hz. Erodibility is inferred from the rate of change in suspended sediment concentration detected in the annulus. The energy-density/wave number spectrum of azimuthal flow showed peaks in the energy spectrum at paddle rotation wave numbers (k) of 14 and 7 m -1 (macroturbulent time scales) but were not significant. Friction velocity ( U*), measured (1) at 1 Hz using a flush-mounted hot-film sensor, and (2) derived from measured velocity profiles in the inner part of the logarithmic layer gave comparable results for Ū* < 0·064 m s -1. At higher values of U*, method (2) underpredicted by up to 20%. Method (1) showed radial increases in Ū* in the annulus for Ū y > 0·32 m s -1. Radial velocity gradients were proportional to ( Ū y - 0·32 m s -1). Maximum radial differences in U* were 10% for Ū y = 0·5 ms -1. Suspended sediment mass concentration ( S) in the annulus resulted in a significant decrease (10·5%) in Ū* derived by method (1) over the range 0< S<208 mg l -1. These decreases were not evident in method (2). Method (1) may, therefore, be subject to changes in stress sensor calibration with changes in S. Subaerial deployments of Sea Carousel caused severe substrate disturbance, water losses, and aeration of the annulus. Submarine deployments produced stable results, though dispersion of turbid flume water took place. Results clearly demonstrated the existence of 'Type I' and 'Type II' erosion documented from laboratory studies.
Advanced superposition methods for high speed turbopump vibration analysis
NASA Technical Reports Server (NTRS)
Nielson, C. E.; Campany, A. D.
1981-01-01
The small, high pressure Mark 48 liquid hydrogen turbopump was analyzed and dynamically tested to determine the cause of high speed vibration at an operating speed of 92,400 rpm. This approaches the design point operating speed of 95,000 rpm. The initial dynamic analysis in the design stage and subsequent further analysis of the rotor only dynamics failed to predict the vibration characteristics found during testing. An advanced procedure for dynamics analysis was used in this investigation. The procedure involves developing accurate dynamic models of the rotor assembly and casing assembly by finite element analysis. The dynamically instrumented assemblies are independently rap tested to verify the analytical models. The verified models are then combined by modal superposition techniques to develop a completed turbopump model where dynamic characteristics are determined. The results of the dynamic testing and analysis obtained are presented and methods of moving the high speed vibration characteristics to speeds above the operating range are recommended. Recommendations for use of these advanced dynamic analysis procedures during initial design phases are given.
Large quantum superpositions of a nanoparticle immersed in superfluid helium
NASA Astrophysics Data System (ADS)
Lychkovskiy, O.
2016-06-01
Preparing and detecting spatially extended quantum superpositions of a massive object comprises an important fundamental test of quantum theory. These quantum states are extremely fragile and tend to quickly decay into incoherent mixtures due to the environmental decoherence. Experimental setups considered up to date address this threat in a conceptually straightforward way—by eliminating the environment, i.e., by isolating an object in a sufficiently high vacuum. We show that another option exists: decoherence is suppressed in the presence of a strongly interacting environment if this environment is superfluid. Indeed, as long as an object immersed in a pure superfluid at zero temperature moves with a velocity below the critical one, it does not create, absorb, or scatter any excitations of the superfluid. Hence, in this idealized situation the decoherence is absent. In reality the decoherence will be present due to thermal excitations of the superfluid and impurities contaminating the superfluid. We examine various decoherence channels in the superfluid
Solar Supergranulation Revealed as a Superposition of Traveling Waves
NASA Technical Reports Server (NTRS)
Gizon, L.; Duvall, T. L., Jr.; Schou, J.; Oegerle, William (Technical Monitor)
2002-01-01
40 years ago two new solar phenomena were described: supergranulation and the five-minute solar oscillations. While the oscillations have since been explained and exploited to determine the properties of the solar interior, the supergranulation has remained unexplained. The supergranules, appearing as convective-like cellular patterns of horizontal outward flow with a characteristic diameter of 30 Mm and an apparent lifetime of 1 day, have puzzling properties, including their apparent superrotation and the minute temperature variations over the cells. Using a 60-day sequence of data from the MDI (Michelson-Doppler Imager) instrument onboard the SOHO (Solar and Heliospheric Observatory) spacecraft, we show that the supergranulation pattern is formed by a superposition of traveling waves with periods of 5-10 days. The wave power is anisotropic with excess power in the direction of rotation and toward the equator, leading to spurious rotation rates and north-south flows as derived from correlation analyses. These newly discovered waves could play an important role in maintaining differential rotation in the upper convection zone by transporting angular momentum towards the equator.
Mechanical Analysis of High Power Internally Cooled Annular Fuel
Zhao Jiyun; No, Hee Cheon; Kazimi, Mujid S.
2004-05-15
Annular fuel with internal flow is proposed to allow higher power density in pressurized water reactors. The structural behavior issues arising from the higher flow rate required to cool the fuel are assessed here, including buckling, vibrations, and potential wear problems. Five flow-induced vibration mechanisms are addressed: buckling instability, vortex-induced vibration, acoustic resonance, fluid-elastic instability, and turbulence-induced vibration. The structural behavior of the 17 x 17 traditional solid fuel array is compared with that of two types of annular fuels, a 15 x 15 array, and a 13 x 13 array.It is seen that the annular fuels are superior to the reference fuel in avoiding vibration-induced damage, even at a 50% increase in flow velocity above today's reactors. The higher resistance to vibration is mainly due to their relatively larger cross section area making them more rigid. The 13 x 13 annular fuel shows better structural performance than the 15 x 15 one due to its higher rigidity. Analysis of acoustic resonance of the inner channel cladding with pump blade passing frequencies showed that the acoustic frequencies are within 120% of the pulsation frequency. The annular fuel exhibits reduced impact, sliding, and fretting wear than the solid fuel, even at 150% flow rate of today's reactors.
New method of annular sub-apertures stitching
NASA Astrophysics Data System (ADS)
Su, Yun; Wang, Kai; Ruan, Ningjuan; Li, Bo
2009-05-01
Annular sub-apertures stitching technology is a feasible method for testing asphere without assistant equipment. The overlap area of two annular sub-apertures is needed to sample in traditional stitching way. The size of overlap area influences the accuracy and efficiency of annular sub-apertures stitching, since small area will deduce the error of calculation, otherwise, more sub-apertures will be needed. Based on the principle of annular sub-apertures interference, a model is built to calculate the parameters of sub-apertures according to equal thickness interference in this paper firstly; then two clear-cut interference areas near the center of asphere and annular sub-apertures are figured out by theory and simulation. A new method is presented to use interference area near the center of asphere as the overlap area to sample. The results of simulation in the paper reveal that this new method can reduce stitching error relatively and improve efficiency availably, solving the inconsistency of error and efficiency consequently.
Non-axisymmetric annular curtain stability
NASA Astrophysics Data System (ADS)
Ahmed, Zahir U.; Khayat, Roger E.; Maissa, Philippe; Mathis, Christian
2013-08-01
A stability analysis of non-axisymmetric annular curtain is carried out for an axially moving viscous jet subject in surrounding viscous gas media. The effect of inertia, surface tension, gas-to-liquid density ratio, inner-to-outer radius ratio, and gas-to-liquid viscosity ratio on the stability of the jet is studied. In general, the axisymmetric disturbance is found to be the dominant mode. However, for small wavenumber, the non-axisymmetric mode is the most unstable mode and the one likely observed in reality. Inertia and the viscosity ratio for non-axisymmetric disturbances show a similar stability influence as observed for axisymmetric disturbances. The maximum growth rate in non-axisymmetric flow, interestingly, appears at very small wavenumber for all inertia levels. The dominant wavenumber increases (decreases) with inertia for non-axisymmetric (axisymmetric) flow. Gas-to-liquid density ratio, curvature effect, and surface tension, however, exhibit an opposite influence on growth rate compared to axisymmetric disturbances. Surface tension tends to stabilize the flow with reductions of the unstable wavenumber range and the maximum growth rate as well as the dominant wavenumber. The dominant wavenumber remains independent of viscosity ratio indicating the viscosity ratio increases the breakup length of the sheet with very little influence on the size of the drops. The range of unstable wavenumbers is affected only by curvature in axisymmetric flow, whereas all the stability parameters control the range of unstable wavenumbers in non-axisymmetric flow. Inertia and gas density increase the unstable wavenumber range, whereas the radius ratio, surface tension, and the viscosity ratio decrease the unstable wavenumber range. Neutral curves are plotted to separate the stable and unstable domains. Critical radius ratio decreases linearly and nonlinearly with the wavenumber for axisymmetric and non-axisymmetric disturbances, respectively. At smaller Weber numbers, a
A reciprocal space approach for locating symmetry elements in Patterson superposition maps
Hendrixson, T.
1990-09-21
A method for determining the location and possible existence of symmetry elements in Patterson superposition maps has been developed. A comparison of the original superposition map and a superposition map operated on by the symmetry element gives possible translations to the location of the symmetry element. A reciprocal space approach using structure factor-like quantities obtained from the Fourier transform of the superposition function is then used to determine the best'' location of the symmetry element. Constraints based upon the space group requirements are also used as a check on the locations. The locations of the symmetry elements are used to modify the Fourier transform coefficients of the superposition function to give an approximation of the structure factors, which are then refined using the EG relation. The analysis of several compounds using this method is presented. Reciprocal space techniques for locating multiple images in the superposition function are also presented, along with methods to remove the effect of multiple images in the Fourier transform coefficients of the superposition map. In addition, crystallographic studies of the extended chain structure of (NHC{sub 5}H{sub 5})SbI{sub 4} and of the twinning method of the orthorhombic form of the high-{Tc} superconductor YBa{sub 2}Cu{sub 3}O{sub 7-x} are presented. 54 refs.
Cohen, Philip R; Carlos, Casey A
2015-07-01
Granuloma annulare, a benign dermatosis of undetermined etiology, typically presents in a localized or generalized form. It has 3 distinctive histologic patterns: an infiltrative (interstitial) pattern, a palisading granuloma pattern, and an epithelioid nodule (sarcoidal granuloma) pattern. A man whose granuloma annulare skin lesions mimicked sarcoidosis is described. His localized granuloma annulare presented with a total of 3 lesions that each had a distinctive clinical morphology: an annular lesion of individual papules, a dermal nodule, and a linear arrangement of 3 papules. Two of his lesions showed a palisading granuloma histology pattern of granuloma annulare; however, the linear papules on his posterior neck lesion demonstrated noncaseating granulomas consistent with either the epithelioid nodule histology pattern of granuloma annulare or sarcoidal granuloma compatible with sarcoidosis. A comprehensive evaluation excluded the diagnosis of systemic sarcoidosis. Using the PubMed database, an extensive literature search was performed on granuloma annulare, epithelioid nodule, sarcoidal granuloma, and sarcoidosis. The histology patterns of granuloma annulare-emphasizing the history and differentiating features of the epithelioid nodule pattern from cutaneous sarcoidosis-were reviewed. The epithelioid nodule (sarcoidal granuloma) histology pattern of granuloma annulare is uncommon and may mimic the histology changes observed in sarcoidosis skin lesions; the absence of asteroid or other giant cell inclusions and an increase in mucin deposition between the collagen bundles favor the diagnosis of granuloma annulare. In addition, the epithelioid nodule pattern of granuloma annulare can rarely also show other histologic patterns of granuloma annulare in the same biopsy specimen or concurrently present with other clinical lesions of granuloma annulare that demonstrate a palisading granuloma, or possibly an infiltrative, histology pattern. However, the presence of an
Design and analysis of annular antenna arrays with different reflectors.
Shi, G; Joines, W T
2004-09-01
The design and performance of annular antenna arrays with reflectors is presented. Arrays with three shapes of reflectors are analysed and simulated. These include the corner reflector, the circular reflector and the elliptical reflector. Power-density distributions within the annular arrays with and without reflectors are obtained by using the FDTD method. Also, the image theory method is used to verify the FDTD results in one case. By comparing the power-density distribution pattern of all four of the array designs (three with different reflectors, one without reflector), it is readily seen in each case that the array with reflectors yields better power-efficiency than the array without reflectors and the elliptical reflector yields the best performance. Comparisons of each array are made using 4, 6 and 8 antennae in the annular array. By using the optimized results of the elliptical reflector, the requirement for the input-power level to each antenna is greatly reduced. PMID:15370818
Derivation of anisotropic diffusion coefficients in a large annular cavity
Eiichi Suetomi; Hiroshi Sekimoto )
1993-06-01
A small reactor for a spacecraft or a small liquid-metal reactor for urban siting, decentralized electrical units, or seawater desalination is designed for a large leakage of neutrons from the reactor core. In these reactors, a movable annular reflector is used for reactivity control. Therefore, a large annular cavity exists between the core and the shielding materials. In this paper, anisotropic diffusion coefficients for a large annular cavity are derived by equating the neutron currents obtained by the diffusion equation and by the transport equation. These diffusion coefficients depend only on the geometrical configuration of the cavity. A numerical comparison of diffusion calculations using these diffusion coefficients and transport calculations shows good agreement.
Annular subaperture interferometric testing technique for large aspheric surfaces
NASA Astrophysics Data System (ADS)
Hou, Xi; Wu, Fan; Wu, Shibin; Chen, Qiang
2005-02-01
A new method to test large aspheric surface by using Annular Sub-aperture Interferometric Testing (ASIT) is described in this paper. It solves the two main difficulties, which are manufacture difficulty and high cost of auxiliary elements (optics compensator, CGH, large reflector) used generally in testing the large aspheric mirror. The method reduces departure between the reference wavefront and tested wavefront to the measurement range of the interferometer by testing annular subaperture of aspheric surface, which makes reference wavefronts with different curvature radius match corresponding annular subaperture, then sews all sub-aperture datum together with a suitable algorithm to get the whole information of the surface. A stitching mathematics model is provided. The feasibility of the technique has been demonstrated by comparing test results from an autocollimation test and ASIT of an 152-mm diameter paraboloidal mirror. This method extends the dynamic range of interferometric measurements, by which the large, fast aspheric surface can be directly tested without additional optical elements.
Imaging performance of annular apertures. II - Line spread functions
NASA Technical Reports Server (NTRS)
Tschunko, H. F. A.
1978-01-01
Line images formed by aberration-free optical systems with annular apertures are investigated in the whole range of central obstruction ratios. Annular apertures form lines images with central and side line groups. The number of lines in each line group is given by the ratio of the outer diameter of the annular aperture divided by the width of the annulus. The theoretical energy fraction of 0.889 in the central line of the image formed by an unobstructed aperture increases for centrally obstructed apertures to 0.932 for the central line group. Energy fractions for the central and side line groups are practically constant for all obstruction ratios and for each line group. The illumination of rectangular secondary apertures of various length/width ratios by apertures of various obstruction ratios is discussed.
The Annular Gap: Gamma-Ray & Radio Emission of Pulsars
NASA Astrophysics Data System (ADS)
Qiao, G. J.; Du, Y. J.; Han, J. L.; Xu, R. X.
2013-01-01
Pulsars have been found more than 40 years. Observations from radio to gamma-rays present abundant information. However, the radiation mechanism is still an open question. It is found that the annular gap could be formed in the magnetosphere of pulsars (neutron stars or quark stars), which combines the advantages of the polar cap, slot gap and outer gap models. It is emphasized that observations of some radio pulsars, normal and millisecond gamma-ray pulsars (MSGPs) show that the annular gap would play a very important role. Here we show some observational and theoretical evidences about the annular gap. For example, bi-drifting sub-pulses; radio and gamma-ray millisecond pulsars and so on.
The principle of superposition and its application in ground-water hydraulics
Reilly, Thomas E.; Franke, O. Lehn; Bennett, Gordon D.
1987-01-01
The principle of superposition, a powerful mathematical technique for analyzing certain types of complex problems in many areas of science and technology, has important applications in ground-water hydraulics and modeling of ground-water systems. The principle of superposition states that problem solutions can be added together to obtain composite solutions. This principle applies to linear systems governed by linear differential equations. This report introduces the principle of superposition as it applies to ground-water hydrology and provides background information, discussion, illustrative problems with solutions, and problems to be solved by the reader.
The principle of superposition and its application in ground-water hydraulics
Reilly, T.E.; Franke, O.L.; Bennett, G.D.
1984-01-01
The principle of superposition, a powerful methematical technique for analyzing certain types of complex problems in many areas of science and technology, has important application in ground-water hydraulics and modeling of ground-water systems. The principle of superposition states that solutions to individual problems can be added together to obtain solutions to complex problems. This principle applies to linear systems governed by linear differential equations. This report introduces the principle of superposition as it applies to groundwater hydrology and provides background information, discussion, illustrative problems with solutions, and problems to be solved by the reader. (USGS)
Yukawa, Mitsuyoshi; Miyata, Kazunori; Mizuta, Takahiro; Yonezawa, Hidehiro; Marek, Petr; Filip, Radim; Furusawa, Akira
2013-03-11
We develop an experimental scheme based on a continuous-wave (cw) laser for generating arbitrary superpositions of photon number states. In this experiment, we successfully generate superposition states of zero to three photons, namely advanced versions of superpositions of two and three coherent states. They are fully compatible with developed quantum teleportation and measurement-based quantum operations with cw lasers. Due to achieved high detection efficiency, we observe, without any loss correction, multiple areas of negativity of Wigner function, which confirm strongly nonclassical nature of the generated states. PMID:23482124
A convolution-superposition dose calculation engine for GPUs
Hissoiny, Sami; Ozell, Benoit; Despres, Philippe
2010-03-15
Purpose: Graphic processing units (GPUs) are increasingly used for scientific applications, where their parallel architecture and unprecedented computing power density can be exploited to accelerate calculations. In this paper, a new GPU implementation of a convolution/superposition (CS) algorithm is presented. Methods: This new GPU implementation has been designed from the ground-up to use the graphics card's strengths and to avoid its weaknesses. The CS GPU algorithm takes into account beam hardening, off-axis softening, kernel tilting, and relies heavily on raytracing through patient imaging data. Implementation details are reported as well as a multi-GPU solution. Results: An overall single-GPU acceleration factor of 908x was achieved when compared to a nonoptimized version of the CS algorithm implemented in PlanUNC in single threaded central processing unit (CPU) mode, resulting in approximatively 2.8 s per beam for a 3D dose computation on a 0.4 cm grid. A comparison to an established commercial system leads to an acceleration factor of approximately 29x or 0.58 versus 16.6 s per beam in single threaded mode. An acceleration factor of 46x has been obtained for the total energy released per mass (TERMA) calculation and a 943x acceleration factor for the CS calculation compared to PlanUNC. Dose distributions also have been obtained for a simple water-lung phantom to verify that the implementation gives accurate results. Conclusions: These results suggest that GPUs are an attractive solution for radiation therapy applications and that careful design, taking the GPU architecture into account, is critical in obtaining significant acceleration factors. These results potentially can have a significant impact on complex dose delivery techniques requiring intensive dose calculations such as intensity-modulated radiation therapy (IMRT) and arc therapy. They also are relevant for adaptive radiation therapy where dose results must be obtained rapidly.
Annular elastolytic giant cell granuloma in association with Hashimoto's thyroiditis
Hassan, Rishi; Arunprasath, P.; Padmavathy, L.; Srivenkateswaran, K.
2016-01-01
Annular elastolytic giant cell granuloma (AEGCG) is a rare granulomatous skin disease characterized clinically by annular plaques with elevated borders and atrophic centers found mainly on sun-exposed skin and histologically by diffuse granulomatous infiltrates composed of multinucleated giant cells, histiocytes and lymphocytes in the dermis along with phagocytosis of elastic fibers by multinucleated giant cells. We report a case of AEGCG in a 50-year-old woman and is highlighted for the classical clinical and histological findings of the disease and its rare co-existence with Hashimoto's thyroiditis. PMID:27057492
Predictions for the annular solar eclipse of 1984
NASA Technical Reports Server (NTRS)
Espenak, F.
1984-01-01
Predictions for the path of the annular solar eclipse of 30 May 1984 are presented. Local circumstances for cities in and along the path are discussed as well as the Saros history of this eclipse. The author investigates the possibility of observing the solar corona during maximum eclipse but concludes that the prospects are remote. Finally, the appearance of the eclipse during annularity, and beading phenomena, are discussed, with the help of a lunar-limb analysis and observations made at previous eclipses of this Saros series.
Portal annular pancreas: the pancreatic duct ring sign on MRCP
Lath, Chinar O.; Agrawal, Dilpesh S.; Timins, Michael E.; Wein, Melissa M.
2015-01-01
Portal annular pancreas is a rare pancreatic variant in which the uncinate process of the pancreas extends and fuses to the dorsal surface of the body of the pancreas by surrounding the portal vein. It is asymptomatic, but it can be mistaken for a pancreatic head mass on imaging and could also have serious consequences during pancreatic surgery, if unrecognized. We report this case of a 53-year-old female patient who was diagnosed to have portal annular pancreas on the basis of an unusual course (ring appearance) of the main pancreatic duct on magnetic resonance cholangiopancreatography, not described earlier in the radiology literature. PMID:26649117
Annular elastolytic giant cell granuloma in association with Hashimoto's thyroiditis.
Hassan, Rishi; Arunprasath, P; Padmavathy, L; Srivenkateswaran, K
2016-01-01
Annular elastolytic giant cell granuloma (AEGCG) is a rare granulomatous skin disease characterized clinically by annular plaques with elevated borders and atrophic centers found mainly on sun-exposed skin and histologically by diffuse granulomatous infiltrates composed of multinucleated giant cells, histiocytes and lymphocytes in the dermis along with phagocytosis of elastic fibers by multinucleated giant cells. We report a case of AEGCG in a 50-year-old woman and is highlighted for the classical clinical and histological findings of the disease and its rare co-existence with Hashimoto's thyroiditis. PMID:27057492
Portal annular pancreas: the pancreatic duct ring sign on MRCP.
Lath, Chinar O; Agrawal, Dilpesh S; Timins, Michael E; Wein, Melissa M
2015-12-01
Portal annular pancreas is a rare pancreatic variant in which the uncinate process of the pancreas extends and fuses to the dorsal surface of the body of the pancreas by surrounding the portal vein. It is asymptomatic, but it can be mistaken for a pancreatic head mass on imaging and could also have serious consequences during pancreatic surgery, if unrecognized. We report this case of a 53-year-old female patient who was diagnosed to have portal annular pancreas on the basis of an unusual course (ring appearance) of the main pancreatic duct on magnetic resonance cholangiopancreatography, not described earlier in the radiology literature. PMID:26649117
Preceding Annular Skin Lesions in a Patient with Hemophagocytic Lymphohistiocytosis
Jun, Hee Jin; Kim, Hyung Ok; Lee, Jun Young
2015-01-01
The cutaneous manifestations of hemophagocytic lymphohistiocytosis (HLH) are variable and nonspecific. A 42-year-old man presented with multiple annular, erythematous patches on the trunk for 3 months. Two months later, he presented with bullae along with high fever. The laboratory examination showed pancytopenia, hypertriglyceridemia, and hypofibrinogenemia. The bone marrow biopsy specimen showed an active hemophagocytosis. On the basis of these findings, a diagnosis of HLH was concluded. After five cycles of chemotherapy, his skin lesion completely resolved. Taking the results together, we suggest that annular skin lesion can be added to the list of cutaneous manifestations of HLH. PMID:26512177
Polarization-independent waveguiding with annular photonic crystals.
Cicek, Ahmet; Ulug, Bulent
2009-09-28
A linear waveguide in an annular photonic crystal composed of a square array of annular dielectric rods in air is demonstrated to guide transverse electric and transverse magnetic modes simultaneously. Overlapping of the guided bands in the full band gap of the photonic crystal is shown to be achieved through an appropriate set of geometric parameters. Results of Finite-Difference Time-Domain simulations to demonstrate polarization-independent waveguiding with low loss and wavelength-order confinement are presented. Transmission through a 90 degrees bend is also demonstrated. PMID:19907629
Multi-functional annular fairing for coupling launch abort motor to space vehicle
NASA Technical Reports Server (NTRS)
Camarda, Charles J. (Inventor); Scotti, Stephen J. (Inventor); Buning, Pieter G. (Inventor); Bauer, Steven X. S. (Inventor); Engelund, Walter C. (Inventor); Schuster, David M. (Inventor)
2011-01-01
An annular fairing having aerodynamic, thermal, structural and acoustic attributes couples a launch abort motor to a space vehicle having a payload of concern mounted on top of a rocket propulsion system. A first end of the annular fairing is fixedly attached to the launch abort motor while a second end of the annular fairing is attached in a releasable fashion to an aft region of the payload. The annular fairing increases in diameter between its first and second ends.
Intra-cavity generation of a superposition of Bessel-Gauss beams
NASA Astrophysics Data System (ADS)
Wong-Campos, Jaime D.; Hernandez-Aranda, Raul I.
2012-10-01
The generation of intra-cavity superpositions of Bessel-Gauss beams in an axicon resonator is studied numerically by means of a genetic algorithm. The coherent superposition of low order modes is induced by introducing crossed wires within the simulated cavity. Two different strategies are shown to be equivalent for the generation of the same superposition of two Bessel-Gauss beams with opposite azimuthal orders. In the first strategy the angle between a pair of cross-wires is varied for mode selection, the second consists on introducing a number of crosswires at equally spaced angles in which the number of wires corresponds exactly to the order of the superposed modes. Our results suggest a direct method for generating experimentally a coherent mode superposition of Bessel-Gauss beams using an axicon-based Bessel-Gauss resonator. These beams are relevant in areas such as optical trapping and micromanipulatio
On the Use of Material-Dependent Damping in ANSYS for Mode Superposition Transient Analysis
Nie, J.; Wei, X.
2011-07-17
The mode superposition method is often used for dynamic analysis of complex structures, such as the seismic Category I structures in nuclear power plants, in place of the less efficient full method, which uses the full system matrices for calculation of the transient responses. In such applications, specification of material-dependent damping is usually desirable because complex structures can consist of multiple types of materials that may have different energy dissipation capabilities. A recent review of the ANSYS manual for several releases found that the use of material-dependent damping is not clearly explained for performing a mode superposition transient dynamic analysis. This paper includes several mode superposition transient dynamic analyses using different ways to specify damping in ANSYS, in order to determine how material-dependent damping can be specified conveniently in a mode superposition transient dynamic analysis.
Design and Evaluation of a Research-Based Teaching Sequence: The Superposition of Electric Field.
ERIC Educational Resources Information Center
Viennot, L.; Rainson, S.
1999-01-01
Illustrates an approach to research-based teaching strategies and their evaluation. Addresses a teaching sequence on the superposition of electric fields implemented at the college level in an institutional framework subject to severe constraints. Contains 28 references. (DDR)
NASA Technical Reports Server (NTRS)
Roychoudhuri, Chandrasekhar; Prasad, Narasimha S.; Peng, Qing
2007-01-01
Any superposition effect as measured (SEM) by us is the summation of simultaneous stimulations experienced by a detector due to the presence of multiple copies of a detectee each carrying different values of the same parameter. We discus the cases with light beams carrying same frequency for both diffraction and multiple beam Fabry-Perot interferometer and also a case where the two superposed light beams carry different frequencies. Our key argument is that if light really consists of indivisible elementary particle, photon, then it cannot by itself create superposition effect since the state vector of an elementary particle cannot carry more than one values of any parameter at the same time. Fortunately, semiclassical model explains all light induced interactions using quantized atoms and classical EM wave packet. Classical physics, with its deeper commitment to Reality Ontology, was better prepared to nurture the emergence of Quantum Mechanics and still can provide guidance to explore nature deeper if we pay careful attention to successful classical formulations like Huygens-Fresnel diffraction integral.
Spagnolo, Nicolo; Sciarrino, Fabio; De Martini, Francesco
2010-09-15
We show that the quantum states generated by universal optimal quantum cloning of a single photon represent a universal set of quantum superpositions resilient to decoherence. We adopt the Bures distance as a tool to investigate the persistence of quantum coherence of these quantum states. According to this analysis, the process of universal cloning realizes a class of quantum superpositions that exhibits a covariance property in lossy configuration over the complete set of polarization states in the Bloch sphere.